Substituted cyclohexanones

ABSTRACT

Disclosed herein are substituted cyclohexanone-based NMDA receptor modulators of Formula I, process of preparation thereof, pharmaceutical compositions thereof, and methods of use thereof.

This application claims the benefit of priority of U.S. provisionalapplication No. 60/914,121, filed Apr. 26, 2007, the disclosure of whichis hereby incorporated by reference as if written herein in itsentirety.

FIELD

The present invention is directed to cyclohexanone-based N-methyld-aspartate (NMDA) receptor modulators, pharmaceutically acceptablesalts and prodrugs thereof, the chemical synthesis thereof, and medicaluse of such compounds for the treatment and/or management of NMDAreceptor-mediated disorders.

BACKGROUND

Ketamine (Ketalor®, Ketaject®, Ketalar®) is a putative uncompetitiveantagonist of calcium, sodium, and potassium transport through theN-methyl d-aspartate (NMDA) receptor. Ketamine binds at an allostericsite on the NDMA receptor. Ketamine is used to induce and maintaindissociative anesthesia and analgesia. Ketamine and othermechanistically similar agents, such as phencyclidine (PCP), amantadine,ibogaine, nitrous oxide, and dextromethorphan, are frequentlyco-administered with benzodiazepines (and triazolobenzodiazepines).Ketamine has a synergistic effect with opioids. Since many non-NMDAanesthetic agents modulate vascular tone, blood pressure, andrespiration, their utility is governed by the presence and provision ofartificial ventilation and cardiac function drugs. NMDA receptorantagonists do not suffer from this drawback. Ketamine induced effectsare rapid, but they are short lived (Grant et al, British journal ofAnaesthesiology 1983, 55, 1107-1111; Anderson et al, Biomedicine &Pharmacotherapy 2006, 60, 303-309; Clements et al, Journal ofPharmaceutical Sciences 1982, 71(5), 539-542; Hyjazi et al, BritishJournal of Anaesthesia 2003, 90(2), 155-160; Mazar et al, Anesthesiology2005, 102, 1174-1181; Obach, Drug Metabolism and Disposition 1999,27(11), 1350-1359; Persson et al, European Journal of ClinicalPharmacology 2002, 57, 869-875; White et al, British Journal ofAnaesthesia 1985, 57, 197-203; Yanagihara et al, Biopharmaceutics & DrugDisposition 2003, 24, 37-43.

The half-life of ketamine can range from about two to about five hours,depending on the mode of administration. Nasal administration ofKetamine not only increases Ketamine's half life, but also provides ahigher bioavailability than other forms of administration, with Franging from approximately 20% to 50%. Ketamine affords a blood toplasma ratio of ˜0.82 and readily crosses the blood brain barrier.Ketamine has two enantiomers, each with unique characteristics. TheS-(+) isomer is approximately four times more potent than the R-(−)isomer. Each enantiomer has a similar half-life. The S-(+) isomer isreported to be superior in inducing anesthesia, leads to a fasterrecovery, and has a lower incidence of emergence delirium. S-(+) isomeradministration, however, causes more overall side-effects, but theside-effects are considered minor. Ketamine's role in neuroprotectionand neurodegradation is ambiguous. Acute ketamine use can provideneuroprotection by increasing cerebral blood flow, thereby hinderingcerebral ischemia progression, and by maintaining normal cardiacparameters during administration. On the other hand, long-term ketamineuse causes vacuole formation in animals, which has been linked toneurodegration. It is not clear, however, whether vacuole formationresults from the action of the parent drug itself or from the action ofone of its metabolites. Ketamine is subject to extensive first-passmetabolism, mainly through oxidation catalyzed by CYP3A4. A primarymetabolite of Ketamine is N-desmethylketamine, usually referred to as“norketamine.” Norketamine is roughly one third as potent as the parentdrug and has a half-life of about five hours. Another detectedmetabolite, dehydronorketamine, may be a contaminant as opposed to anactual in vivo metabolite. Much of the excreted material consists ofglucuronidated and hydroxylated material.

SUMMARY OF THE INVENTION

Disclosed herein is a compound having structural Formula I:

or a pharmaceutically acceptable salt, solvate, or prodrug thereof;wherein:

R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, andR₁₆ are independently selected from the group consisting of hydrogen anddeuterium; and

at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃,R₁₄, R₁₅, and R₁₆ is deuterium.

Further disclosed herein is a method for treating, preventing, orameliorating one or more symptoms of a NMDA receptor-mediated disorderwhich comprises administering to a subject a therapeutically effectiveamount of at least one compound as disclosed herein or apharmaceutically acceptable salt, solvate, or prodrug thereof.

Additionally disclosed herein is a method for treating, preventing, orameliorating one or more symptoms of a disorder involving, but notlimited to, nociceptive pain, neuropathic pain, phantom limb pain,ischemic pain, stroke, sepsis, inflammation, opioid tolerance,Alzheimer's disease, burn, any disorder which can lessened, alleviated,or benefited by administering an anesthetic, analgesic, entheogen,therapeutic cataleptic, or neuroprotective agent, and/or any disorderwhich can lessened, alleviated, or benefited by modulating NMDAreceptors.

Also disclosed herein are articles of manufacture and kits containingcompounds as disclosed herein. By way of example only a kit or articleof manufacture can include a container (such as a bottle) with a desiredamount of at least one compound (or pharmaceutical composition of acompound) as disclosed herein. Further, such a kit or article ofmanufacture can further include instructions for using said compound (orpharmaceutical composition of a compound) disclosed herein. Theinstructions can be attached to the container, or can be included in apackage (such as a box or a plastic or foil bag) holding the container.

In another aspect is the use of a compound as disclosed herein in themanufacture of a medicament for treating a disorder in a subject, bymodulating NMDA receptors. In a further or alternative embodiment, saiddisorder is nociceptive pain, neuropathic pain, phantom limb pain,ischemic pain, stroke, sepsis, inflammation, opioid tolerance,Alzheimer's disease, burn, any disorder which can lessened, alleviated,or benefited by administering an anesthetic, analgesic, entheogen,therapeutic cataleptic, or neuroprotective agent, and/or any disorderwhich can lessened, alleviated, or benefited by modulating NMDAreceptors.

In another aspect are processes for preparing a compound as disclosedherein as a NMDA receptor modulator, or other pharmaceuticallyacceptable derivatives such as prodrug derivatives, or individualisomers and mixture of isomers or enantiomers thereof.

Also disclosed herein are processes for formulating pharmaceuticalcompositions with a compound disclosed herein.

In further embodiments, said pharmaceutical composition comprises acompound disclosed herein and one or more pharmaceutically acceptablecarriers.

In certain embodiments said pharmaceutical composition comprises one ormore release-controlling excipients.

In other embodiments said pharmaceutical composition further comprisesone or more non-release controlling excipients.

In certain embodiments said pharmaceutical composition is suitable fororal, parenteral, or intravenous infusion administration.

In yet other embodiments said pharmaceutical composition comprises atablet, or capsule.

In certain embodiments the compounds as disclosed herein areadministered in a dose of 0.5 milligram to 1000 milligram.

In yet further embodiments said pharmaceutical compositions furthercomprise another therapeutic agent.

In other embodiments said therapeutic agent is selected from the groupconsisting of NMDA-receptor modulators, opioids, anesthetics,peripherally acting muscle relaxants, benzodiazepines, endothelinconverting enzyme (ECE) inhibitors, thromboxane enzyme antagonists,potassium channel openers, thrombin inhibitors, growth factorinhibitors, platelet activating factor (PAF) antagonists, anti-plateletagents, Factor VIIa Inhibitors, Factor Xa Inhibitors, renin inhibitors,neutral endopeptidase (NEP) inhibitors, vasopepsidase inhibitors, HMGCoA reductase inhibitors, squalene synthetase inhibitors, fibrates, bileacid sequestrants, anti-atherosclerotic agents, MTP Inhibitors, calciumchannel blockers, potassium channel activators, alpha-PDE5 agents,beta-PDE5 agents, antiarrhythmic agents, diuretics, anti-diabeticagents, PPAR-gamma agonists, mineralocorticoid enzyme antagonists, aP2inhibitors, protein tyrosine kinase inhibitors, antiinflammatories,antiproliferatives, chemotherapeutic agents, immunosuppressants,anticancer agents, cytotoxic agents, antimetabolites, farnesyl-proteintransferase inhibitors, hormonal agents, microtubule-disruptor agents,microtubule-stablizing agents, topoisomerase inhibitors, prenyl-proteintransferase inhibitors, cyclosporins, TNF-alpha inhibitors,cyclooxygenase-2 (COX-2) inhibitors, gold compounds, and platinumcoordination complexes.

In other embodiments said therapeutic agent is a NMDA-receptormodulator.

In further embodiments said NMDA-receptor modulator is selected from thegroup consisting of phencyclidine (PCP), amantadine, ibogaine,memantine, nitrous oxide, and dextromethorphan.

In other embodiments said therapeutic agent is an opioid.

In further embodiments said opioid is selected from the group consistingof morphine, codeine, thebain, diacetylmorphine, oxycodone, hydrocodone,hydromorphone, oxymorphone, nicomorphine, fentanyl, α-methylfentanyl,alfentanil, sufentanil, remifentanyl, carfentanyl, ohmefentanyl,pethidine, ketobemidone, propoxyphene, dextropropoxyphene, methadone,loperamide, pentazocine, buprenorphine, etorphine, butorphanol,nalbutine, levorphanol, naloxone, naltrexone, and tramadol.

In other embodiments said therapeutic agent is an anesthetic.

In yet other embodiments said anesthetic is selected from the groupconsisting of diethyl ether, vinyl ether, halothane, chloroform,methoxyflurane, enflurane, trichloroethylene, isoflurane, desflurane,sevoflurane, methohexital, hexobarbital, thiopental, narcobarbital,fentanyl, alfentanil, sufentanil, phenoperidine, anileridine,remifentanil, droperidol, ketamine, propanidid, alfaxalone, etomidate,propofol, hydroxybutyric acid, nitrous oxide, esketamine,metabutethamine, procaine, tetracaine, chloroprocaine, benzocaine,bupivacaine, lidocaine, mepivacaine, prilocaine, butanilicaine,cinchocaine, etidocaine, articaine, ropivacaine, levobupivacaine,cocaine, ethyl chloride, dyclonine, phenol, and capsaicin.

In other embodiments said therapeutic agent is a peripherally actingmuscle relaxant.

In yet other embodiments said peripherally acting muscle relaxant isselected from the group consisting of alcuronium, dimethyltubocurarine,tubocurarine, suxamethonium, atracurium, cisatracurium, doxacuriumchloride, fazadinium bromide, gallamine, hexafluronium, mivacuriumchloride, pancuronium, pipecuronium bromide, rocuronium bromide,vecuronium, and botulinum toxin.

In other embodiments said therapeutic agent is a benzodiazepine.

In yet other embodiments said benzodiazepine is selected from the groupconsisting of alprazolam, bromazepam, clonazepam, diazepam, estazolam,flunitrazepam, lorazepam, midazolam, nitrazepam, oxazepam, triazolam,temazepam, and chlordiazepoxide.

In further embodiments of the present invention, a method for thetreatment, prevention, or amelioration of one or more symptoms of a NDMAreceptor-mediated disorder in a subject by administering atherapeutically effective amount of a compound as disclosed herein.

In other embodiments said NDMA receptor-mediated disorder is selectedfrom the group consisting of nociceptive pain, neuropathic pain, phantomlimb pain, ischemic pain, stroke, sepsis, inflammation, opioidtolerance, Alzheimer's disease, and burn.

In further embodiments, said NMDA receptor-mediated disorder can belessened, alleviated, or prevented by using an agent selected from thegroup consisting of an anesthetic, analgesic, entheogen, therapeuticcataleptic, and neuroprotectant.

In certain embodiments said anesthetic promotes general anaesthesia.

In yet other embodiments said NMDA receptor-mediated disorder can belessened, alleviated, or prevented by administering a NDMA receptormodulator.

In other embodiments said compound has at least one of the followingproperties:

-   -   a) decreased inter-individual variation in plasma levels of said        compound or a metabolite thereof as compared to the        non-isotopically enriched compound;    -   b) increased average plasma levels of said compound per dosage        unit thereof as compared to the non-isotopically enriched        compound;    -   c) decreased average plasma levels of at least one metabolite of        said compound per dosage unit thereof as compared to the        non-isotopically enriched compound;    -   d) increased average plasma levels of at least one metabolite of        said compound per dosage unit thereof as compared to the        non-isotopically enriched compound; and    -   e) an improved clinical effect during the treatment in said        subject per dosage unit thereof as compared to the        non-isotopically enriched compound.

In yet further embodiments said compound has at least two of thefollowing properties:

-   -   a) decreased inter-individual variation in plasma levels of said        compound or a metabolite thereof as compared to the        non-isotopically enriched compound;    -   b) increased average plasma levels of said compound per dosage        unit thereof as compared to the non-isotopically enriched        compound;    -   c) decreased average plasma levels of at least one metabolite of        said compound per dosage unit thereof as compared to the        non-isotopically enriched compound;    -   d) increased average plasma levels of at least one metabolite of        said compound per dosage unit thereof as compared to the        non-isotopically enriched compound; and    -   e) an improved clinical effect during the treatment in said        subject per dosage unit thereof as compared to the        non-isotopically enriched compound.

In certain embodiments said compound has a decreased metabolism by atleast one polymorphically-expressed cytochrome P₄₅₀ isoform in saidsubject per dosage unit thereof as compared to the non-isotopicallyenriched compound.

In other embodiments said cytochrome P₄₅₀ isoform is selected from thegroup consisting of CYP2C8, CYP2C9, CYP2C19, and CYP2D6.

In yet further embodiments said compound is characterized by decreasedinhibition of at least one cytochrome P₄₅₀ or monoamine oxidase isoformin said subject per dosage unit thereof as compared to thenon-isotopically enriched compound.

In certain embodiments said cytochrome P₄₅₀ or monoamine oxidase isoformis selected from the group consisting of CYP1A1, CYP1A2, CYP1B1, CYP2A6,CYP2A13, CYP2B6, CYP2C8, CYP2C9, CYP2C18, CYP2C19, CYP2D6, CYP2E1,CYP2G1, CYP2J2, CYP2R1, CYP2S1, CYP3A4, CYP3A5, CYP3A5P1, CYP3A5P2,CYP3A7, CYP4A11, CYP4B1, CYP4F2, CYP4F3, CYP4F8, CYP4F11, CYP4F12,CYP4X1, CYP4Z1, CYP5A1, CYP7A1, CYP7B1, CYP8A1, CYP8B1, CYP11A1,CYP11B1, CYP11B2, CYP17, CYP19, CYP21, CYP24, CYP26A1, CYP26B1, CYP27A1,CYP27B1, CYP39, CYP46, CYP51, MAOA, and MAOB.

In other embodiments said method method affects the treatment of thedisorder while reducing or eliminating a deleterious change in adiagnostic hepatobiliary function endpoint, as compared to thecorresponding non-isotopically enriched compound.

In yet further embodiments said diagnostic hepatobiliary functionendpoint is selected from the group consisting of alanineaminotransferase (“ALT”), serum glutamic-pyruvic transaminase (“SGPT”),aspartate aminotransferase (“AST,” “SGOT”), ALT/AST ratios, serumaldolase, alkaline phosphatase (“ALP”), ammonia levels, bilirubin,gamma-glutamyl transpeptidase (“GGTP,” “γ-GTP,” “GGT”), leucineaminopeptidase (“LAP”), liver biopsy, liver ultrasonography, livernuclear scan, 5′-nucleotidase, and blood protein.

INCORPORATION BY REFERENCE

All publications and references cited herein, including those in thebackground section, are expressly incorporated herein by reference intheir entirety. However, with respect to any similar or identical termsfound in both the incorporated publications or references and thoseexpressly put forth or defined in this document, then those termsdefinitions or meanings expressly put forth in this document shallcontrol in all respects.

DETAILED DESCRIPTION

To facilitate understanding of the disclosure set forth herein, a numberof terms are defined below. Generally, the nomenclature used herein andthe laboratory procedures in organic chemistry, medicinal chemistry, andpharmacology described herein are those well known and commonly employedin the art. Unless defined otherwise, all technical and scientific termsused herein generally have the same meaning as commonly understood inthe art to which this disclosure belongs. In the event that there is aplurality of definitions for a term used herein, those in this sectionprevail unless stated otherwise.

As used herein, the singular forms “a,” “an,” and “the” may refer toplural articles unless specifically stated otherwise.

The term “subject” refers to an animal, including, but not limited to, aprimate (e.g., human monkey, chimpanzee, gorilla, and the like), rodents(e.g., rats, mice, gerbils, hamsters, ferrets, and the like),lagomorphs, swine (e.g., pig, miniature pig), equine, canine, feline,and the like. The terms “subject” and “patient” are used interchangeablyherein in reference, for example, to a mammalian subject, such as ahuman patient.

The terms “treat,” “treating,” and “treatment” are meant to includealleviating or abrogating a disorder; or alleviating or abrogating oneor more of the symptoms associated with the disorder; and/or alleviatingor eradicating the cause(s) of the disorder itself.

The terms “prevent,” “preventing,” and “prevention” refer to a method ofdelaying or precluding the onset of a disorder; delaying or precludingits attendant symptoms; barring a subject from acquiring a disorder;and/or reducing a subject's risk of acquiring a disorder.

The term “therapeutically effective amount” refers to the amount of acompound that, when administered, is sufficient to prevent developmentof, or alleviate to some extent, one or more of the symptoms of thedisorder being treated. The term “therapeutically effective amount” alsorefers to the amount of a compound that is sufficient to elicit thebiological or medical response of a cell, tissue, system, animal, orhuman that is being sought by a researcher, veterinarian, medicaldoctor, or clinician.

The term “pharmaceutically acceptable carrier,” “pharmaceuticallyacceptable excipient,” “physiologically acceptable carrier,” or“physiologically acceptable excipient” refers to apharmaceutically-acceptable material, composition, or vehicle, such as aliquid or solid filler, diluent, excipient, solvent, or encapsulatingmaterial. Each component must be “pharmaceutically acceptable” in thesense of being compatible with the other ingredients of a pharmaceuticalformulation. It must also be suitable for use in contact with the tissueor organ of humans and animals without excessive toxicity, irritation,allergic response, immunogenecity, or other problems or complications,commensurate with a reasonable benefit/risk ratio. See, Remington: TheScience and Practice of Pharmacy, 21st Edition; Lippincott Williams &Wilkins: Philadelphia, Pa., 2005; Handbook of Pharmaceutical Excipients,5th Edition; Rowe et al., Eds., The Pharmaceutical Press and theAmerican Pharmaceutical Association: 2005; and Handbook ofPharmaceutical Additives, 3rd Edition; Ash and Ash Eds., GowerPublishing Company: 2007; Pharmaceutical Preformulation and Formulation,Gibson Ed., CRC Press LLC: Boca Raton, Fla., 2004).

The term “deuterium enrichment” refers to the percentage ofincorporation of deuterium at a given position in a molecule in theplace of hydrogen. For example, deuterium enrichment of 1% at a givenposition means that 1% of molecules in a given sample contain deuteriumat the specified position. Because the naturally occurring distributionof deuterium is about 0.0156%, deuterium enrichment at any position in acompound synthesized using non-enriched starting materials is about0.0156%. The deuterium enrichment can be determined using conventionalanalytical methods, such as mass spectrometry and nuclear magneticresonance spectroscopy.

The term “is/are deuterium,” when used to describe a given position in amolecule such as R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃,R₁₄, R₁₅, and R₁₆ or the symbol “D,” when used to represent a givenposition in a drawing of a molecular structure, means that the specifiedposition is enriched with deuterium above the naturally occurringdistribution of deuterium. In an embodiment deuterium enrichment is ofno less than about 1%, in another no less than about 5%, in another noless than about 10%, in another no less than about 20%, in another noless than about 50%, in another no less than about 70%, in another noless than about 80%, in another no less than about 90%, or in another noless than about 98% of deuterium at the specified position.

The term “isotopic enrichment” refers to the percentage of incorporationof a less prevalent isotope of an element at a given position in amolecule in the place of the more prevalent isotope of the element.

The term “non-isotopically enriched” refers to a molecule in which thepercentages of the various isotopes are substantially the same as thenaturally occurring percentages.

The terms “substantially pure” and “substantially homogeneous” meansufficiently homogeneous to appear free of readily detectable impuritiesas determined by standard analytical methods, including, but not limitedto, thin layer chromatography (TLC), gel electrophoresis, highperformance liquid chromatography (HPLC), nuclear magnetic resonance(NMR), and mass spectrometry (MS); or sufficiently pure such thatfurther purification would not detectably alter the physical andchemical properties, or biological and pharmacological properties, suchas enzymatic and biological activities, of the substance. In certainembodiments, “substantially pure” or “substantially homogeneous” refersto a collection of molecules, wherein at least about 50%, at least about70%, at least about 80%, at least about 90%, at least about 95%, atleast about 98%, at least about 99%, or at least about 99.5% of themolecules are a single compound, including a racemic mixture or singlestereoisomer thereof, as determined by standard analytical methods.

The term “about” or “approximately” means an acceptable error for aparticular value, which depends in part on how the value is measured ordetermined. In certain embodiments, “about” can mean 1 or more standarddeviations.

The terms “active ingredient” and “active substance” refer to acompound, which is administered, alone or in combination with one ormore pharmaceutically acceptable excipients and/or carriers, to asubject for treating, preventing, or ameliorating one or more symptomsof a disorder.

The terms “drug,” “therapeutic agent,” and “chemotherapeutic agent”refer to a compound, or a pharmaceutical composition thereof, which isadministered to a subject for treating, preventing, or ameliorating oneor more symptoms of a disorder.

The term “disorder” as used herein is intended to be generallysynonymous, and is used interchangeably with, the terms “disease,”“sydrome” and “condition” (as in medical condition), in that all reflectan abnormal condition of the body or of one of its parts that impairsnormal functioning and is typically manifested by distinguishing signsand symptoms.

The term “release controlling excipient” refers to an excipient whoseprimary function is to modify the duration or place of release of theactive substance from a dosage form as compared with a conventionalimmediate release dosage form.

The term “nonrelease controlling excipient” refers to an excipient whoseprimary function do not include modifying the duration or place ofrelease of the active substance from a dosage form as compared with aconventional immediate release dosage form.

The term “NMDA” refers to the N-methyl d-aspartate receptor, a proteinthat facilitates the transport of ions, particularly calcium, sodium,and potassium, across certain cell membranes.

The term “NMDA receptor-mediated disorder,” refers to a disorder that ischaracterized by abnormal NMDA receptor activity or normal NMDA receptoractivity that, when that activity is modified, leads to the ameliorationof other abnormal biological processes. An NMDA receptor-mediateddisorder may be completely or partially mediated by the abnormal NMDAreceptor. In particular, a NMDA receptor-mediated disorder is one inwhich modulation of the NMDA receptor activity results in some effect onthe underlying disorder, e.g., an NMDA receptor modulator results insome improvement in at least some of the patients being treated.

The term “NMDA receptor modulator” or “modulation of NMDA receptors”refers to the ability of a compound disclosed herein to alter thefunction of an NMDA receptor. A modulator may activate the activity ofan NMDA receptor, may activate or inhibit the activity of an NMDAreceptor depending on the concentration of the compound exposed to theNMDA receptor, or may inhibit the activity of an NMDA receptor. Suchactivation or inhibition may be contingent on the occurrence of aspecific event, such as activation of a signal transduction pathway,and/or may be manifest only in particular cell types. The term “NMDAreceptor modulator” or “modulation of NMDA receptors” also refers toaltering the function of an NMDA receptor by increasing or decreasingthe probability that a complex forms between an NMDA receptor and anatural binding partner. A NDMA receptor modulator may increase theprobability that such a complex forms between the NMDA receptor and thenatural binding partner, may increase or decrease the probability that acomplex forms between the NMDA receptor and the natural binding partnerdepending on the concentration of the compound exposed to the NMDAreceptor, and or may decrease the probability that a complex formsbetween the NMDA receptor and the natural binding partner. In someembodiments, modulation of the NMDA receptor may be assessed usingReceptor Selection and Amplification Technology (R-SAT) as described inU.S. Pat. No. 5,707,798, the disclosure of which is incorporated hereinby reference in its entirety.

The term “protecting group” or “removable protecting group” refers to agroup which, when bound to a functionality, such as the oxygen atom of ahydroxyl or carboxyl group, or the nitrogen atom of an amino group,prevents reactions from occurring at that functional group, and whichcan be removed by a conventional chemical or enzymatic step toreestablish the functional group (Greene and Wuts, Protective Groups inOrganic Synthesis, 3^(rd) Ed., John Wiley & Sons, New York, N.Y., 1999).

The term “halogen”, “halide” or “halo” includes fluorine, chlorine,bromine, and iodine.

The term “leaving group” (LG) refers to any atom (or group of atoms)that is stable in its anion or neutral form after it has been displacedby a nucleophile. The definition of “leaving group” includes but is notlimited to: water, methanol, ethanol, chloride, bromide, iodide, analkylsulfonate, for example methanesulfonate, ethanesulfonate and thelike, an arylsulfonate, for example benzenesulfonate, tolylsulfonate andthe like, a perhaloalkanesulfonate, for exampletrifluoromethanesulfonate, trichloromethanesulfonate and the like, analkylcarboxylate, for example acetate and the like, aperhaloalkylcarboxylate, for example trifluoroacetate, trichloroacetateand the like, an arylcarboxylate, for example benzoate and the like.

The term “brominating reagent” refers to a reactive chemical reagentused in bromination reactions, whereby bromine is transferred to asubstrate. Examples of chlorinating agents include, but are not limitedto, copper(II) bromide, tetrabromomethan, N-bromosuccinimide,hydrobromic acid, 1,3-dibromo-5,5-dimethylhydantoin, phosphorustribromide, bromine chloride, gaseous bromine, sulfuryl bromide, liquidbromine, and aluminum tribromide.

The terms “alkyl” and “substituted alkyl” are interchangeable andinclude substituted, optionally substituted and unsubstituted C₁-C₁₀straight chain saturated aliphatic hydrocarbon groups, substituted,optionally substituted and unsubstituted C₂-C₁₀ straight chainunsaturated aliphatic hydrocarbon groups, substituted, optionallysubstituted and unsubstituted C₂-C₁₀ branched saturated aliphatichydrocarbon groups, substituted and unsubstituted C₂-C₁₀ branchedunsaturated aliphatic hydrocarbon groups, substituted, optionallysubstituted and unsubstituted C₃-C₈ cyclic saturated aliphatichydrocarbon groups, substituted, optionally substituted andunsubstituted C₅-C₈ cyclic unsaturated aliphatic hydrocarbon groupshaving the specified number of carbon atoms. For example, the definitionof “alkyl” shall include but is not limited to: methyl (Me),trideuteromethyl (—CD₃), ethyl (Et), propyl (Pr), butyl (Bu), pentyl,hexyl, heptyl, octyl, nonyl, decyl, undecyl, ethenyl, propenyl, butenyl,penentyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl,isopropyl (i-Pr), isobutyl (i-Bu), tert-butyl (t-Bu), sec-butyl (s-Bu),isopentyl, neopentyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,cycloheptyl, cyclooctyl, cyclopentenyl, cyclohexenyl, cycloheptenyl,cyclooctenyl, methylcyclopropyl, ethylcyclohexenyl, butenylcyclopentyl,adamantyl, norbornyl and the like. Alkyl substituents are independentlyselected from the group consisting of hydrogen, deuterium, halogen, —OH,—SH, —NH₂, —CN, —NO₂, ═O, ═CH₂, trihalomethyl, carbamoyl,arylC₀₋₁₀alkyl, heteroarylC₀₋₁₀alkyl, C₁₋₁₀alkyloxy, arylC₀₋₁₀alkyloxy,C₁₋₁₀alkylthio, arylC₀₋₁₀alkylthio, C₁₋₁₀alkylamino,arylC₀₋₁₀alkylamino, N-aryl-N—C₀₋₁₀alkylamino, C₁₋₁₀alkylcarbonyl,arylC₀₋₁₀alkylcarbonyl, C₁₋₁₀alkylcarboxy, arylC₀₋₁₀alkylcarboxy,C₁₋₁₀alkylcarbonylamino, arylC₀₋₁₀alkylcarbonylamino, tetrahydrofuryl,morpholinyl, piperazinyl, hydroxypyronyl, —C₀₋₁₀alkylCOOR₃₀ and—C₀₋₁₀alkylCONR₃₁R₃₂ wherein R₃₀, R₃₁ and R₃₂ are independently selectedfrom the group consisting of hydrogen, deuterium, alkyl, aryl, or R₃₂and R₃₃ are taken together with the nitrogen to which they are attachedforming a saturated cyclic or unsaturated cyclic system containing 3 to8 carbon atoms with at least one substituent as defined herein.

In light of the purposes described in the present disclosure, allreferences to “alkyl” groups or any groups ordinarily containing C—Hbonds may include partially or fully deuterated versions as required toaffect the improvements outlined herein.

Deuterium Kinetic Isotope Effect

In an attempt to eliminate foreign substances, such as therapeuticagents, from its circulation system, the animal body expresses variousenzymes, such as the cytochrome P₄₅₀ enzymes or CYPs, esterases,proteases, reductases, dehydrogenases, and monoamine oxidases, to reactwith and convert these foreign substances to more polar intermediates ormetabolites for renal excretion. Some of the most common metabolicreactions of pharmaceutical compounds involve the oxidation of acarbon-hydrogen (C—H) bond to either a carbon-oxygen (C—O) orcarbon-carbon (C—C) π-bond. The resultant metabolites may be stable orunstable under physiological conditions, and can have substantiallydifferent pharmacokinetic, pharmacodynamic, and acute and long-termtoxicity profiles relative to the parent compounds. For most drugs, suchoxidations are generally rapid and ultimately lead to administration ofmultiple or high daily doses.

The relationship between the activation energy and the rate of reactionmay be quantified by the Arrhenius equation, k=Ae^(−Eact/RT), whereE_(act) is the activation energy, T is temperature, R is the molar gasconstant, k is the rate constant for the reaction, and A (the frequencyfactor) is a constant specific to each reaction that depends on theprobability that the molecules will collide with the correctorientation. The Arrhenius equation states that the fraction ofmolecules that have enough energy to overcome an energy barrier, thatis, those with energy at least equal to the activation energy, dependsexponentially on the ratio of the activation energy to thermal energy(RT), the average amount of thermal energy that molecules possess at acertain temperature.

The transition state in a reaction is a short lived state (on the orderof 10⁻¹⁴ sec) along the reaction pathway during which the original bondshave stretched to their limit. By definition, the activation energyE_(act) for a reaction is the energy required to reach the transitionstate of that reaction. Reactions that involve multiple steps willnecessarily have a number of transition states, and in these instances,the activation energy for the reaction is equal to the energy differencebetween the reactants and the most unstable transition state. Once thetransition state is reached, the molecules can either revert, thusreforming the original reactants, or the new bonds form giving rise tothe products. This dichotomy is possible because both pathways, forwardand reverse, result in the release of energy. A catalyst facilitates areaction process by lowering the activation energy leading to atransition state. Enzymes are examples of biological catalysts thatreduce the energy necessary to achieve a particular transition state.

A carbon-hydrogen bond is by nature a covalent chemical bond. Such abond forms when two atoms of similar electronegativity share some oftheir valence electrons, thereby creating a force that holds the atomstogether. This force or bond strength can be quantified and is expressedin units of energy, and as such, covalent bonds between various atomscan be classified according to how much energy must be applied to thebond in order to break the bond or separate the two atoms.

The bond strength is directly proportional to the absolute value of theground-state vibrational energy of the bond. This vibrational energy,which is also known as the zero-point vibrational energy, depends on themass of the atoms that form the bond. The absolute value of thezero-point vibrational energy increases as the mass of one or both ofthe atoms making the bond increases. Since deuterium (D) is two-foldmore massive than hydrogen (H), it follows that a C-D bond is strongerthan the corresponding C—H bond. Compounds with C-D bonds are frequentlyindefinitely stable in H₂O, and have been widely used for isotopicstudies. If a C—H bond is broken during a rate-determining step in achemical reaction (i.e. the step with the highest transition stateenergy), then substituting a deuterium for that hydrogen will cause adecrease in the reaction rate and the process will slow down. Thisphenomenon is known as the Deuterium Kinetic Isotope Effect (DKIE) andcan range from about 1 (no isotope effect) to very large numbers, suchas 50 or more, meaning that the reaction can be fifty, or more, timesslower when deuterium is substituted for hydrogen. High DKIE values maybe due in part to a phenomenon known as tunneling, which is aconsequence of the uncertainty principle. Tunneling is ascribed to thesmall size of a hydrogen atom, and occurs because transition statesinvolving a proton can sometimes form in the absence of the requiredactivation energy. A deuterium is larger and statistically has a muchlower probability of undergoing this phenomenon. Substitution of tritiumfor hydrogen results in yet a stronger bond than deuterium and givesnumerically larger isotope effects.

Discovered in 1932 by Urey, deuterium (D) is a stable andnon-radioactive isotope of hydrogen. It was the first isotope to beseparated from its element in pure form and is twice as massive ashydrogen, and makes up about 0.02% of the total mass of hydrogen (inthis usage meaning all hydrogen isotopes) on earth. When two deuteriumsbond with one oxygen, deuterium oxide (D₂O or “heavy water”) is formed.D₂O looks and tastes like H₂O, but has different physical properties. Itboils at 101.41° C. and freezes at 3.79° C. Its heat capacity, heat offusion, heat of vaporization, and entropy are all higher than H₂O. It isalso more viscous and is not as powerful a solvent as H₂O.

When pure D₂O is given to rodents, it is readily absorbed and reaches anequilibrium level that is usually about eighty percent of theconcentration of what was consumed. The quantity of deuterium requiredto induce toxicity is extremely high. When 0% to as much as 15% of thebody water has been replaced by D₂O, animals are healthy but are unableto gain weight as fast as the control (untreated) group. When about 15%to about 20% of the body water has been replaced with D₂O, the animalsbecome excitable. When about 20% to about 25% of the body water has beenreplaced with D₂O, the animals are so excitable that they go intofrequent convulsions when stimulated. Skin lesions, ulcers on the pawsand muzzles, and necrosis of the tails appear. The animals also becomevery aggressive; males becoming almost unmanageable. When about 30%, ofthe body water has been replaced with D₂O, the animals refuse to eat andbecome comatose. Their body weight drops sharply and their metabolicrates drop far below normal, with death occurring at about 30 to about35% replacement with D₂O. The effects are reversible unless more thanthirty percent of the previous body weight has been lost due to D₂O.Studies have also shown that the use of D₂O can delay the growth ofcancer cells and enhance the cytotoxicity of certain antineoplasticagents.

Tritium (T) is a radioactive isotope of hydrogen, used in research,fusion reactors, neutron generators and radiopharmaceuticals. Mixingtritium with a phosphor provides a continuous light source, a techniquethat is commonly used in wristwatches, compasses, rifle sights and exitsigns. It was discovered by Rutherford, Oliphant and Harteck in 1934,and is produced naturally in the upper atmosphere when cosmic rays reactwith H₂ molecules. Tritium is a hydrogen atom that has 2 neutrons in thenucleus and has an atomic weight close to 3. It occurs naturally in theenvironment in very low concentrations, most commonly found as T₂O, acolorless and odorless liquid. Tritium decays slowly (half-life=12.3years) and emits a low energy beta particle that cannot penetrate theouter layer of human skin. Internal exposure is the main hazardassociated with this isotope, yet it must be ingested in large amountsto pose a significant health risk. As compared with deuterium, a lesseramount of tritium must be consumed before it reaches a hazardous level.

Deuteration of pharmaceuticals to improve pharmacokinetics (PK),pharmacodynamics (PD), and toxicity profiles, has been demonstratedpreviously with some classes of drugs. For example, DKIE was used todecrease the hepatotoxicity of halothane by presumably limiting theproduction of reactive species such as trifluoroacetyl chloride.However, this method may not be applicable to all drug classes. Forexample, deuterium incorporation can lead to metabolic switching whichmay even give rise to an oxidative intermediate with a faster off-ratefrom an activating Phase I enzyme (e.g., cytochrome P₄₅₀ 3A4). Theconcept of metabolic switching asserts that xenogens, when sequesteredby Phase I enzymes, may bind transiently and re-bind in a variety ofconformations prior to the chemical reaction (e.g., oxidation). Thishypothesis is supported by the relatively vast size of binding pocketsin many Phase I enzymes and the promiscuous nature of many metabolicreactions. Metabolic switching can potentially lead to differentproportions of known metabolites as well as altogether new metabolites.This new metabolic profile may impart more or less toxicity. Suchpitfalls are non-obvious and have not been heretofore sufficientlypredictable a priori for any drug class.

Deuterated Cyclohexanone Derivatives

Ketamine is a substituted cyclohexanone-based NMDA antagonist. Thecarbon-hydrogen bonds of ketamine contain a naturally occurringdistribution of hydrogen isotopes, namely ¹H or protium (about99.9844%), ²H or deuterium (about 0.0156%), and ³H or tritium (in therange between about 0.5 and 67 tritium atoms per 10¹⁸ protium atoms).Increased levels of deuterium incorporation may produce a detectableKinetic Isotope Effect (KIE) that could affect the pharmacokinetic,pharmacologic and/or toxicologic profiles of NMDA modulators incomparison with the compound having naturally occurring levels ofdeuterium.

The primary ketamine metabolites in humans result from the demethylationof the N-methyl group and by the hydroxylation of the cyclohexanonegroup. Other metabolites may also exist, including metabolites arisingfrom oxidation of ketamine's aromatic ring C—H bonds. The toxicity andpharmacology of the resultant aforementioned metabolite/s are not knownwith certainty but oxidation of the C—H bonds may lead to the formationof reactive metabolites which can be toxic. Limiting the production ofsuch metabolites has the potential to decrease the danger of theadministration of such drugs and may even allow increased dosage andconcomitant increased efficacy. Various deuteration patterns can be usedto a) reduce or eliminate unwanted metabolites, b) increase thehalf-life of the parent drug, c) decrease the number of doses needed toachieve a desired effect, d) decrease the amount of a dose needed toachieve a desired effect, e) increase the formation of activemetabolites, if any are formed, and/or f) decrease the production ofdeleterious metabolites in specific tissues and/or create a moreeffective drug and/or a safer drug for polypharmacy, whether thepolypharmacy be intentional or not. The deuteration approach has strongpotential to slow the metabolism via various oxidative mechanisms.

In one embodiment, disclosed herein is a compound having structuralFormula I:

or a pharmaceutically acceptable salt, solvate, or prodrug thereof;wherein:

R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, andR₁₆ are independently selected from the group consisting of hydrogen anddeuterium; and

at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃,R₁₄, R₁₅, and R₁₆ is deuterium.

In another embodiment, at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈,R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ independently has deuteriumenrichment of no less than about 1%, no less than about 5%, no less thanabout 10%, no less than about 20%, no less than about 50%, no less thanabout 70%, no less than about 80%, no less than about 90%, or no lessthan about 98%.

In a further embodiment, said compound is substantially a singleenantiomer, a mixture of about 90% or more by weight of the(−)-enantiomer and about 10% or less by weight of the (+)-enantiomer, amixture of about 90% or more by weight of the (+)-enantiomer and about10% or less by weight of the (−)-enantiomer, substantially an individualdiastereomer, or a mixture of about 90% or more by weight of anindividual diastereomer and about 10% or less by weight of any otherdiastereomer.

In other embodiments, R₁ is hydrogen. In some embodiments, R₂ ishydrogen. In other embodiments, R₃ is hydrogen. In yet otherembodiments, R₄ is hydrogen. In yet other embodiments, R₅ is hydrogen.In yet other embodiments, R₆ is hydrogen. In still other embodiments, R₇is hydrogen. In still other embodiments, R₈ is hydrogen. In someembodiments, R₉ is hydrogen. In other embodiments, R₁₀ is hydrogen. Inyet other embodiments, R₁₁ is hydrogen. In still other embodiments, R₁₂is hydrogen. In yet other embodiments, R₁₃ is hydrogen. In otherembodiments, R₁₄ is hydrogen. In certain embodiments, R₁₅ is hydrogen.In other embodiments, R₁₆ is hydrogen.

In other embodiments, R₁ is deuterium. In some embodiments, R₂ isdeuterium. In other embodiments, R₃ is deuterium. In yet otherembodiments, R₄ is deuterium. In yet other embodiments, R₅ is deuterium.In yet other embodiments, R₆ is deuterium. In still other embodiments,R₇ is deuterium. In still other embodiments, R₈ is deuterium. In someembodiments, R₉ is deuterium. In other embodiments, R₁₀ is deuterium. Inyet other embodiments, R₁₁ is deuterium. In still other embodiments, R₁₂is deuterium. In yet other embodiments, R₁₃ is deuterium. In otherembodiments, R₁₄ is deuterium. In certain embodiments, R₁₅ is deuterium.In other embodiments, R₁₆ is deuterium.

In yet another embodiment, at least one of R₁, R₂, R₃, R₄, R₅, and R₆ isdeuterium.

In yet another embodiment, R₁, R₂, R₃, R₄, R₅, and R₆ are deuterium.

In yet another embodiment, at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇,and R₈ is deuterium.

In yet another embodiment, R₁, R₂, R₃, R₄, R₅, R₆, R₇, and R₈ aredeuterium

In yet another embodiment, at least one of R₉, R₁₀, and R₁₁ isdeuterium.

In yet another embodiment, R₉, R₁₀, and R₁₁ are deuterium.

In yet another embodiment, R₁₂ is deuterium.

In yet another embodiment, at least one of R₁₃, R₁₄, R₁₅, and R₁₆ isdeuterium.

In yet another embodiment, R₁₃, R₁₄, R₁₅, and R₁₆ are deuterium.

In yet another embodiment, at least one of R₁, R₂, R₃, R₄, R₅, and R₆ isdeuterium; and R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ arehydrogen.

In yet another embodiment, R₁, R₂, R₃, R₄, R₅, and R₆ are deuterium; andR₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ are hydrogen.

In yet another embodiment, at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇,and R₈, deuterium; and R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ arehydrogen.

In yet another embodiment, R₁, R₂, R₃, R₄, R₅, R₆, R₇, and R₈ aredeuterium R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ are hydrogen.

In yet another embodiment, at least one of R₉, R₁₀, and R₁₁ isdeuterium; and R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₁₂, R₁₃, R₁₄, R₁₅, andR₁₆ are hydrogen.

In yet another embodiment, R₉, R₁₀, and R₁₁ are deuterium; and R₁, R₂,R₃, R₄, R₅, R₆, R₇, R₈, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ are hydrogen.

In yet another embodiment, R₁₂ is deuterium; and R₁, R₂, R₃, R₄, R₅, R₆,R₇, R₈, R₉, R₁₀, R₁₁, R₁₃, R₁₄, R₁₅, and R₁₆ are hydrogen.

In yet another embodiment, at least one of R₁₃, R₁₄, R₁₅, and R₁₆ isdeuterium; and R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, and R₁₂ arehydrogen.

In yet another embodiment, R₁₃, R₁₄, R₁₅, and R₁₆ are deuterium; and R₁,R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, and R₁₂ are hydrogen.

In yet another embodiment, the compound as disclosed herein is selectedfrom the group consisting of:

or a pharmaceutically acceptable salt, solvate, or prodrug thereof.

In another embodiment, at least one of the positions represented as Dindependently has deuterium enrichment of no less than about 1%, no lessthan about 5%, no less than about 10%, no less than about 20%, no lessthan about 50%, no less than about 70%, no less than about 80%, no lessthan about 90%, or no less than about 98%.

In a further embodiment, said compound is substantially a singleenantiomer, a mixture of about 90% or more by weight of the(−)-enantiomer and about 10% or less by weight of the (+)-enantiomer, amixture of about 90% or more by weight of the (+)-enantiomer and about10% or less by weight of the (−)-enantiomer, substantially an individualdiastereomer, or a mixture of about 90% or more by weight of anindividual diastereomer and about 10% or less by weight of any otherdiastereomer.

In a further embodiment, the compound as disclosed herein is selectedfrom the group consisting of:

In another embodiment, at least one of the positions represented as Dindependently has deuterium enrichment of no less than about 1%, no lessthan about 5%, no less than about 10%, no less than about 20%, no lessthan about 50%, no less than about 70%, no less than about 80%, no lessthan about 90%, or no less than about 98%.

In a further embodiment, said compound is substantially a singleenantiomer, a mixture of about 90% or more by weight of the(−)-enantiomer and about 10% or less by weight of the (+)-enantiomer, amixture of about 90% or more by weight of the (+)-enantiomer and about10% or less by weight of the (−)-enantiomer, substantially an individualdiastereomer, or a mixture of about 90% or more by weight of anindividual diastereomer and about 10% or less by weight of any otherdiastereomer.

In certain embodiments, the compound as disclosed herein contains about60% or more by weight of the (−)-enantiomer of the compound and about40% or less by weight of (+)-enantiomer of the compound. In certainembodiments, the compound as disclosed herein contains about 70% or moreby weight of the (−)-enantiomer of the compound and about 30% or less byweight of (+)-enantiomer of the compound. In certain embodiments, thecompound as disclosed herein contains about 80% or more by weight of the(−)-enantiomer of the compound and about 20% or less by weight of(+)-enantiomer of the compound. In certain embodiments, the compound asdisclosed herein contains about 90% or more by weight of the(−)-enantiomer of the compound and about 10% or less by weight of the(+)-enantiomer of the compound. In certain embodiments, the compound asdisclosed herein contains about 95% or more by weight of the(−)-enantiomer of the compound and about 5% or less by weight of(+)-enantiomer of the compound. In certain embodiments, the compound asdisclosed herein contains about 99% or more by weight of the(−)-enantiomer of the compound and about 1% or less by weight of(+)-enantiomer of the compound.

In certain embodiments, the compound as disclosed herein contains about60% or more by weight of the (+)-enantiomer of the compound and about40% or less by weight of (−)-enantiomer of the compound. In certainembodiments, the compound as disclosed herein contains about 70% or moreby weight of the (+)-enantiomer of the compound and about 30% or less byweight of (−)-enantiomer of the compound. In certain embodiments, thecompound as disclosed herein contains about 80% or more by weight of the(+)-enantiomer of the compound and about 20% or less by weight of(−)-enantiomer of the compound. In certain embodiments, the compound asdisclosed herein contains about 90% or more by weight of the(+)-enantiomer of the compound and about 10% or less by weight of the(−)-enantiomer of the compound. In certain embodiments, the compound asdisclosed herein contains about 95% or more by weight of the(+)-enantiomer of the compound and about 5% or less by weight of(−)-enantiomer of the compound. In certain embodiments, the compound asdisclosed herein contains about 99% or more by weight of the(+)-enantiomer of the compound and about 1% or less by weight of(−)-enantiomer of the compound.

The deuterated compound as disclosed herein may also contain lessprevalent isotopes for other elements, including, but not limited to,¹³C or ¹⁴C for carbon, ³³S, ³⁴S, or ³⁶S for sulfur, ¹⁵N for nitrogen,and ¹⁷O or ¹⁸O for oxygen.

In certain embodiments, without being bound by any theory, the compounddisclosed herein may expose a patient to a maximum of about 0.000005%D₂O or about 0.00001% DHO, assuming that all of the C-D bonds in thecompound as disclosed herein are metabolized and released as D₂O or DHO.This quantity is a small fraction of the naturally occurring backgroundlevels of D₂O or DHO in circulation. In certain embodiments, the levelsof D₂O shown to cause toxicity in animals is much greater than even themaximum limit of exposure because of the deuterium enriched compound asdisclosed herein. Thus, in certain embodiments, the deuterium-enrichedcompound disclosed herein should not cause any additional toxicitybecause of the use of deuterium.

In one embodiment, the deuterated compounds disclosed herein maintainthe beneficial aspects of the corresponding non-isotopically enrichedmolecules while substantially increasing the maximum tolerated dose,decreasing toxicity, increasing the half-life (T_(1/2)), lowering themaximum plasma concentration (C_(max)) of the minimum efficacious dose(MED), lowering the efficacious dose and thus decreasing thenon-mechanism-related toxicity, and/or lowering the probability ofdrug-drug interactions.

Isotopic hydrogen can be introduced into a compound as disclosed hereinby synthetic techniques that employ deuterated reagents, wherebyincorporation rates are pre-determined; and/or by exchange techniques,wherein incorporation rates are determined by equilibrium conditions,and may be highly variable depending on the reaction conditions.Synthetic techniques, where tritium or deuterium is directly andspecifically inserted by tritiated or deuterated reagents of knownisotopic content, may yield high tritium or deuterium abundance, but canbe limited by the chemistry required. Exchange techniques, on the otherhand, may yield lower tritium or deuterium incorporation, often with theisotope being distributed over many sites on the molecule.

The compounds as disclosed herein can be prepared by methods known toone of skill in the art and routine modifications thereof, and/orfollowing procedures similar to those described in the Example sectionherein and routine modifications thereof, and/or procedures found inHopfgartner et al., J. Mass. Spectrom. 1996, 31, 69-76, U.S. Pat. No.3,254,124, and references cited therein and routine modificationsthereof. Compounds as disclosed herein can also be prepared as shown inany of the following schemes and routine modifications thereof.

For example, certain compounds as disclosed herein can be prepared asshown in Scheme 1.

Grignard reagent 2 (prepared from reacting cyclopentylbromide 1 withmagnesium turnings) reacts with 2-chlorobenzonitrile 3, in anappropriate solvent, such as diethyl ether, in the presence of anappropriate catalyst, such copper (I) bromide, to give ketone 4.Compound 4 is then treated with a brominating reagent, such as copper(II) bromine, in an appropriate solvent, such as ethyl acetate, at anelevated temperature to afford bromoketone 5. Compound 5 reacts withaqueous methylamine to give hydroxyimine 6, which then rearranges at anelevated temperature, in an appropriate solvent, such as ethyl benzoate,to give cyclohexanone 7 of Formula I.

Deuterium can be incorporated to different positions synthetically,according to the synthetic procedures as shown in Scheme 1, by usingappropriate deuterated intermediates. For example, to introducedeuterium at one or more positions selected from R₁, R₂, R₃, R₄, R₅, R₆,R₇, and R₈, cyclopentylbromide with the corresponding deuteriumsubstitutions can be used. To introduce deuterium at one or morepositions selected from R₉, R₁₀, and R₁₁, methylamine with thecorresponding deuterium substitutions can be used. To introducedeuterium at one or more positions selected from R₁₃, R₁₄, R₁₅, and R₁₆,2-chlorobenzonitrile with the corresponding deuterium substitutions canbe used. These deuterated intermediates are either commerciallyavailable, or can be prepared by methods known to one of skill in theart or following procedures similar to those described in the Examplesection herein and routine modifications thereof.

Deuterium can also be incorporated to various positions having anexchangeable proton, such as the amine N—H, via proton-deuteriumequilibrium exchange. To introduce deuterium at R₁₂, this proton may bereplaced with deuterium selectively or non-selectively through aproton-deuterium exchange method known in the art.

It is to be understood that the compounds disclosed herein may containone or more chiral centers, chiral axes, and/or chiral planes, asdescribed in “Stereochemistry of Carbon Compounds” Eliel and Wilen, JohnWiley & Sons, New York, 1994, pp. 1119-1190. Such chiral centers, chiralaxes, and chiral planes may be of either the (R) or (S) configuration,or may be a mixture thereof.

Another method for characterizing a composition containing a compoundhaving at least one chiral center is by the effect of the composition ona beam of polarized light. When a beam of plane polarized light ispassed through a solution of a chiral compound, the plane ofpolarization of the light that emerges is rotated relative to theoriginal plane. This phenomenon is known as optical activity, andcompounds that rotate the plane of polarized light are said to beoptically active. One enantiomer of a compound will rotate the beam ofpolarized light in one direction, and the other enantiomer will rotatethe beam of light in the opposite direction. The enantiomer that rotatesthe polarized light in the clockwise direction is the (+) enantiomer,and the enantiomer that rotates the polarized light in thecounterclockwise direction is the (−) enantiomer. Included within thescope of the compositions described herein are compositions containingbetween 0 and 100% of the (+) and/or (−) enantiomer of compoundsdisclosed herein.

Where a compound as disclosed herein contains an alkenyl or alkenylenegroup, the compound may exist as one or mixture of geometric cis/trans(or Z/E) isomers. Where structural isomers are interconvertible via alow energy barrier, the compound disclosed herein may exist as a singletautomer or a mixture of tautomers. This can take the form of protontautomerism in the compound disclosed herein that contains for example,an imino, keto, or oxime group; or so-called valence tautomerism in thecompound that contain an aromatic moiety. It follows that a singlecompound may exhibit more than one type of isomerism.

The compounds disclosed herein may be enantiomerically pure, such as asingle enantiomer or a single diastereomer, or be stereoisomericmixtures, such as a mixture of enantiomers, a racemic mixture, or adiastereomeric mixture. As such, one of skill in the art will recognizethat administration of a compound in its (R) form is equivalent, forcompounds that undergo epimerization in vivo, to administration of thecompound in its (S) form. Conventional techniques for thepreparation/isolation of individual enantiomers include chiral synthesisfrom a suitable optically pure precursor or resolution of the racemateusing, for example, chiral chromatography, recrystallization,resolution, diastereomeric salt formation, or derivatization intodiastereomeric adducts followed by separation.

When the compound disclosed herein contains an acidic or basic moiety,it may also disclosed as a pharmaceutically acceptable salt (See, Bergeet al., J. Pharm. Sci. 1977, 66, 1-19; and “Handbook of PharmaceuticalSalts, Properties, and Use,” Stah and Wermuth, Ed.; Wiley-VCH and VHCA,Zurich, 2002).

Suitable acids for use in the preparation of pharmaceutically acceptablesalts include, but are not limited to, acetic acid, 2,2-dichloroaceticacid, acylated amino acids, adipic acid, alginic acid, ascorbic acid,L-aspartic acid, benzenesulfonic acid, benzoic acid, 4-acetamidobenzoicacid, boric acid, (+)-camphoric acid, camphorsulfonic acid,(+)-(1S)-camphor-10-sulfonic acid, capric acid, caproic acid, caprylicacid, cinnamic acid, citric acid, cyclamic acid, cyclohexanesulfamicacid, dodecylsulfuric acid, ethane-1,2-disulfonic acid, ethanesulfonicacid, 2-hydroxy-ethanesulfonic acid, formic acid, fumaric acid,galactaric acid, gentisic acid, glucoheptonic acid, D-gluconic acid,D-glucuronic acid, L-glutamic acid, α-oxo-glutaric acid, glycolic acid,hippuric acid, hydrobromic acid, hydrochloric acid, hydroiodic acid,(+)-L-lactic acid, (±)-DL-lactic acid, lactobionic acid, lauric acid,maleic acid, (−)-L-malic acid, malonic acid, (±)-DL-mandelic acid,methanesulfonic acid, naphthalene-2-sulfonic acid,naphthalene-1,5-disulfonic acid, 1-hydroxy-2-naphthoic acid, nicotinicacid, nitric acid, oleic acid, orotic acid, oxalic acid, palmitic acid,pamoic acid, perchloric acid, phosphoric acid, L-pyroglutamic acid,saccharic acid, salicylic acid, 4-amino-salicylic acid, sebacic acid,stearic acid, succinic acid, sulfuric acid, tannic acid, (+)-L-tartaricacid, thiocyanic acid, p-toluenesulfonic acid, undecylenic acid, andvaleric acid.

Suitable bases for use in the preparation of pharmaceutically acceptablesalts, including, but not limited to, inorganic bases, such as magnesiumhydroxide, calcium hydroxide, potassium hydroxide, zinc hydroxide, orsodium hydroxide; and organic bases, such as primary, secondary,tertiary, and quaternary, aliphatic and aromatic amines, includingL-arginine, benethamine, benzathine, choline, deanol, diethanolamine,diethylamine, dimethylamine, dipropylamine, diisopropylamine,2-(diethylamino)-ethanol, ethanolamine, ethylamine, ethylenediamine,isopropylamine, N-methyl-glucamine, hydrabamine, 1H-imidazole, L-lysine,morpholine, 4-(2-hydroxyethyl)-morpholine, methylamine, piperidine,piperazine, propylamine, pyrrolidine, 1-(2-hydroxyethyl)-pyrrolidine,pyridine, quinuclidine, quinoline, isoquinoline, secondary amines,triethanolamine, trimethylamine, triethylamine, N-methyl-D-glucamine,2-amino-2-(hydroxymethyl)-1,3-propanediol, and tromethamine.

The compound as disclosed herein may also be designed as a prodrug,which is a functional derivative of the compound as disclosed herein andis readily convertible into the parent compound in vivo. Prodrugs areoften useful because, in some situations, they may be easier toadminister than the parent compound. They may, for instance, bebioavailable by oral administration whereas the parent compound is not.The prodrug may also have enhanced solubility in pharmaceuticalcompositions over the parent compound. A prodrug may be converted intothe parent drug by various mechanisms, including enzymatic processes andmetabolic hydrolysis. See Harper, Progress in Drug Research 1962, 4,221-294; Morozowich et al. in “Design of Biopharmaceutical Propertiesthrough Prodrugs and Analogs,” Roche Ed., APHA Acad. Pharm. Sci. 1977;“Bioreversible Carriers in Drug in Drug Design, Theory and Application,”Roche Ed., APHA Acad. Pharm. Sci. 1987; “Design of Prodrugs,” Bundgaard,Elsevier, 1985; Wang et al., Curr. Pharm. Design 1999, 5, 265-287;Pauletti et al., Adv. Drug. Delivery Rev. 1997, 27, 235-256; Mizen etal., Pharm. Biotech. 1998, 11, 345-365; Gaignault et al., Pract. Med.Chem. 1996, 671-696; Asgharnejad in “Transport Processes inPharmaceutical Systems,” Amidon et al., Ed., Marcell Dekker, 185-218,2000; Balant et al., Eur. J. Drug Metab. Pharmacokinet. 1990, 15,143-53; Balimane and Sinko, Adv. Drug Delivery Rev. 1999, 39, 183-209;Browne, Clin. Neuropharmacol. 1997, 20, 1-12; Bundgaard, Arch. Pharm.Chem. 1979, 86, 1-39; Bundgaard, Controlled Drug Delivery 1987, 17,179-96; Bundgaard, Adv. Drug Delivery Rev. 1992, 8, 1-38; Fleisher etal., Adv. Drug Delivery Rev. 1996, 19, 115-130; Fleisher et al., MethodsEnzymol. 1985, 112, 360-381; Farquhar et al., J. Pharm. Sci. 1983, 72,324-325; Freeman et al., J. Chem. Soc., Chem. Commun. 1991, 875-877;Friis and Bundgaard, Eur. J. Pharm. Sci. 1996, 4, 49-59; Gangwar et al.,Des. Biopharm. Prop. Prodrugs Analogs, 1977, 409-421; Nathwani and Wood,Drugs 1993, 45, 866-94; Sinhababu and Thakker, Adv. Drug Delivery Rev.1996, 19, 241-273; Stella et al., Drugs 1985, 29, 455-73; Tan et al.,Adv. Drug Delivery Rev. 1999, 39, 117-151; Taylor, Adv. Drug DeliveryRev. 1996, 19, 131-148; Valentino and Borchardt, Drug Discovery Today1997, 2, 148-155; Wiebe and Knaus, Adv. Drug Delivery Rev. 1999, 39,63-80; Waller et al., Br. J. Clin. Pharmac. 1989, 28, 497-507.

Pharmaceutical Composition

Disclosed herein are pharmaceutical compositions comprising a compoundas disclosed herein as an active ingredient, or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof, in a pharmaceuticallyacceptable vehicle, carrier, diluent, or excipient, or a mixturethereof; in combination with one or more pharmaceutically acceptableexcipients or carriers.

Disclosed herein are pharmaceutical compositions in modified releasedosage forms, which comprise a compound as disclosed herein, or apharmaceutically acceptable salt, solvate, or prodrug thereof; and oneor more release controlling excipients or carriers as described herein.Suitable modified release dosage vehicles include, but are not limitedto, hydrophilic or hydrophobic matrix devices, water-soluble separatinglayer coatings, enteric coatings, osmotic devices, multiparticulatedevices, and combinations thereof. The pharmaceutical compositions mayalso comprise non-release controlling excipients or carriers.

Further disclosed herein are pharmaceutical compositions in entericcoated dosage forms, which comprise a compound as disclosed herein, or apharmaceutically acceptable salt, solvate, or prodrug thereof; and oneor more release controlling excipients or carriers for use in an entericcoated dosage form. The pharmaceutical compositions may also comprisenon-release controlling excipients or carriers.

Further disclosed herein are pharmaceutical compositions in effervescentdosage forms, which comprise a compound as disclosed herein, or apharmaceutically acceptable salt, solvate, or prodrug thereof; and oneor more release controlling excipients or carriers for use in aneffervescent dosage form. The pharmaceutical compositions may alsocomprise non-release controlling excipients or carriers.

Additionally disclosed are pharmaceutical compositions in a dosage formthat has an instant releasing component and at least one delayedreleasing component, and is capable of giving a discontinuous release ofthe compound in the form of at least two consecutive pulses separated intime from 0.1 up to 24 hours. The pharmaceutical compositions comprise acompound as disclosed herein, or a pharmaceutically acceptable salt,solvate, or prodrug thereof; and one or more release controlling andnon-release controlling excipients or carriers, such as those excipientsor carriers suitable for a disruptable semi-permeable membrane and asswellable substances.

Disclosed herein also are pharmaceutical compositions in a dosage formfor oral administration to a subject, which comprise a compound asdisclosed herein, or a pharmaceutically acceptable salt, solvate, orprodrug thereof; and one or more pharmaceutically acceptable excipientsor carriers, enclosed in an intermediate reactive layer comprising agastric juice-resistant polymeric layered material partially neutralizedwith alkali and having cation exchange capacity and a gastricjuice-resistant outer layer.

Disclosed herein are pharmaceutical compositions that comprise about 0.1to about 1000 mg, about 1 to about 500 mg, about 2 to about 100 mg,about 1 mg, about 2 mg, about 3 mg, about 5 mg, about 10 mg, about 20mg, about 30 mg, about 40 mg, about 50 mg, about 100 mg, about 500 mg ofone or more compounds as disclosed herein in the form of enteric-coatedgranules, as delayed-release capsules for oral administration. Thepharmaceutical compositions further comprise cellulose, disodiumhydrogen phosphate, hydroxypropyl cellulose, hypromellose, lactose,mannitol, and sodium lauryl sulfate.

Disclosed herein are pharmaceutical compositions that comprise about 0.1to about 1000 mg, about 1 to about 500 mg, about 2 to about 100 mg,about 1 mg, about 2 mg, about 3 mg, about 5 mg, about 10 mg, about 20mg, about 30 mg, about 40 mg, about 50 mg, about 100 mg, about 500 mg ofone or more compounds as disclosed herein in the form of enteric-coatedpellets, as delayed-release capsules for oral administration. Thepharmaceutical compositions further comprise glyceryl monostearate40-50, hydroxypropyl cellulose, hypromellose, magnesium stearate,methacrylic acid copolymer type C, polysorbate 80, sugar spheres, talc,and triethyl citrate.

Disclosed herein are pharmaceutical compositions that comprise about 0.1to about 1000 mg, about 1 to about 500 mg, about 2 to about 100 mg,about 1 mg, about 2 mg, about 3 mg, about 5 mg, about 10 mg, about 20mg, about 30 mg, about 40 mg, about 50 mg, about 100 mg, about 500 mg ofone or more compounds as disclosed herein, as enteric-coateddelayed-release tablets for oral administration. The pharmaceuticalcompositions further comprise carnauba wax, crospovidone, diacetylatedmonoglycerides, ethylcellulose, hydroxypropyl cellulose, hypromellosephthalate, magnesium stearate, mannitol, sodium hydroxide, sodiumstearyl fumarate, talc, titanium dioxide, and yellow ferric oxide.

Disclosed herein are pharmaceutical compositions that comprise about 0.1to about 1000 mg, about 1 to about 500 mg, about 2 to about 100 mg,about 1 mg, about 2 mg, about 3 mg, about 5 mg, about 10 mg, about 20mg, about 30 mg, about 40 mg, about 50 mg, about 100 mg, about 500 mg ofone or more compounds as disclosed herein, as enteric-coateddelayed-release tablets for oral administration. The pharmaceuticalcompositions further comprise calcium stearate, crospovidone,hydroxypropyl methylcellulose, iron oxide, mannitol, methacrylic acidcopolymer, polysorbate 80, povidone, propylene glycol, sodium carbonate,sodium lauryl sulfate, titanium dioxide, and triethyl citrate.

The pharmaceutical compositions disclosed herein may be disclosed inunit-dosage forms or multiple-dosage forms. Unit-dosage forms, as usedherein, refer to physically discrete units suitable for administrationto human and animal subjects and packaged individually as is known inthe art. Each unit-dose contains a predetermined quantity of the activeingredient(s) sufficient to produce the desired therapeutic effect, inassociation with the required pharmaceutical carriers or excipients.Examples of unit-dosage forms include ampouls, syringes, andindividually packaged tablets and capsules. Unit-dosage forms may beadministered in fractions or multiples thereof. A multiple-dosage formis a plurality of identical unit-dosage forms packaged in a singlecontainer to be administered in segregated unit-dosage form. Examples ofmultiple-dosage forms include vials, bottles of tablets or capsules, orbottles of pints or gallons.

The compound as disclosed herein may be administered alone, or incombination with one or more other compounds disclosed herein, one ormore other active ingredients. The pharmaceutical compositions thatcomprise a compound disclosed herein may be formulated in various dosageforms for oral, parenteral, and topical administration. Thepharmaceutical compositions may also be formulated as a modified releasedosage form, including delayed-, extended-, prolonged-, sustained-,pulsatile-, controlled-, accelerated- and fast-, targeted-,programmed-release, and gastric retention dosage forms. These dosageforms can be prepared according to conventional methods and techniquesknown to those skilled in the art (see, Remington: The Science andPractice of Pharmacy, supra; Modified-Release Drug Deliver Technology,Rathbone et al., Eds., Drugs and the Pharmaceutical Science, MarcelDekker, Inc.: New York, N.Y., 2002; Vol. 126).

The pharmaceutical compositions disclosed herein may be administered atonce, or multiple times at intervals of time. It is understood that theprecise dosage and duration of treatment may vary with the age, weight,and condition of the patient being treated, and may be determinedempirically using known testing protocols or by extrapolation from invivo or in vitro test or diagnostic data. It is further understood thatfor any particular individual, specific dosage regimens should beadjusted over time according to the individual need and the professionaljudgment of the person administering or supervising the administrationof the formulations.

In the case wherein the patient's condition does not improve, upon thedoctor's discretion the administration of the compounds may beadministered chronically, that is, for an extended period of time,including throughout the duration of the patient's life in order toameliorate or otherwise control or limit the symptoms of the patient'sdisease or condition.

In the case wherein the patient's status does improve, upon the doctor'sdiscretion the administration of the compounds may be given continuouslyor temporarily suspended for a certain length of time (i.e., a “drugholiday”).

Once improvement of the patient's conditions has occurred, a maintenancedose is administered if necessary. Subsequently, the dosage or thefrequency of administration, or both, can be reduced, as a function ofthe symptoms, to a level at which the improved disease, disorder orcondition is retained. Patients can, however, require intermittenttreatment on a long-term basis upon any recurrence of symptoms.

A. Oral Administration

The pharmaceutical compositions disclosed herein may be formulated insolid, semisolid, or liquid dosage forms for oral administration. Asused herein, oral administration also include buccal, lingual, andsublingual administration. Suitable oral dosage forms include, but arenot limited to, tablets, capsules, pills, troches, lozenges, pastimes,cachets, pellets, medicated chewing gum, granules, bulk powders,effervescent or non-effervescent powders or granules, solutions,emulsions, suspensions, solutions, wafers, sprinkles, elixirs, andsyrups. In addition to the active ingredient(s), the pharmaceuticalcompositions may contain one or more pharmaceutically acceptablecarriers or excipients, including, but not limited to, binders, fillers,diluents, disintegrants, wetting agents, lubricants, glidants, coloringagents, dye-migration inhibitors, sweetening agents, and flavoringagents.

Binders or granulators impart cohesiveness to a tablet to ensure thetablet remaining intact after compression. Suitable binders orgranulators include, but are not limited to, starches, such as cornstarch, potato starch, and pre-gelatinized starch (e.g., STARCH 1500);gelatin; sugars, such as sucrose, glucose, dextrose, molasses, andlactose; natural and synthetic gums, such as acacia, alginic acid,alginates, extract of Irish moss, Panwar gum, ghatti gum, mucilage ofisabgol husks, carboxymethylcellulose, methylcellulose,polyvinylpyrrolidone (PVP), Veegum, larch arabogalactan, powderedtragacanth, and guar gum; celluloses, such as ethyl cellulose, celluloseacetate, carboxymethyl cellulose calcium, sodium carboxymethylcellulose, methyl cellulose, hydroxyethylcellulose (HEC),hydroxypropylcellulose (HPC), hydroxypropyl methyl cellulose (HPMC);microcrystalline celluloses, such as AVICEL-PH-101, AVICEL-PH-103,AVICEL RC-581, AVICEL-PH-105 (FMC Corp., Marcus Hook, Pa.); and mixturesthereof. Suitable fillers include, but are not limited to, talc, calciumcarbonate, microcrystalline cellulose, powdered cellulose, dextrates,kaolin, mannitol, silicic acid, sorbitol, starch, pre-gelatinizedstarch, and mixtures thereof. The binder or filler may be present fromabout 50 to about 99% by weight in the pharmaceutical compositionsdisclosed herein.

Suitable diluents include, but are not limited to, dicalcium phosphate,calcium sulfate, lactose, sorbitol, sucrose, inositol, cellulose,kaolin, mannitol, sodium chloride, dry starch, and powdered sugar.Certain diluents, such as mannitol, lactose, sorbitol, sucrose, andinositol, when present in sufficient quantity, can impart properties tosome compressed tablets that permit disintegration in the mouth bychewing. Such compressed tablets can be used as chewable tablets.

Suitable disintegrants include, but are not limited to, agar; bentonite;celluloses, such as methylcellulose and carboxymethylcellulose; woodproducts; natural sponge; cation-exchange resins; alginic acid; gums,such as guar gum and Veegum HV; citrus pulp; cross-linked celluloses,such as croscarmellose; cross-linked polymers, such as crospovidone;cross-linked starches; calcium carbonate; microcrystalline cellulose,such as sodium starch glycolate; polacrilin potassium; starches, such ascorn starch, potato starch, tapioca starch, and pre-gelatinized starch;clays; aligns; and mixtures thereof. The amount of disintegrant in thepharmaceutical compositions disclosed herein varies upon the type offormulation, and is readily discernible to those of ordinary skill inthe art. The pharmaceutical compositions disclosed herein may containfrom about 0.5 to about 15% or from about 1 to about 5% by weight of adisintegrant.

Suitable lubricants include, but are not limited to, calcium stearate;magnesium stearate; mineral oil; light mineral oil; glycerin; sorbitol;mannitol; glycols, such as glycerol behenate and polyethylene glycol(PEG); stearic acid; sodium lauryl sulfate; talc; hydrogenated vegetableoil, including peanut oil, cottonseed oil, sunflower oil, sesame oil,olive oil, corn oil, and soybean oil; zinc stearate; ethyl oleate; ethyllaureate; agar; starch; lycopodium; silica or silica gels, such asAEROSIL® 200 (W.R. Grace Co., Baltimore, Md.) and CAB-O-SIL® (Cabot Co.of Boston, Mass.); and mixtures thereof. The pharmaceutical compositionsdisclosed herein may contain about 0.1 to about 5% by weight of alubricant.

Suitable glidants include colloidal silicon dioxide, CAB-O-SIL® (CabotCo. of Boston, Mass.), and asbestos-free talc. Coloring agents includeany of the approved, certified, water soluble FD&C dyes, and waterinsoluble FD&C dyes suspended on alumina hydrate, and color lakes andmixtures thereof. A color lake is the combination by adsorption of awater-soluble dye to a hydrous oxide of a heavy metal, resulting in aninsoluble form of the dye. Flavoring agents include natural flavorsextracted from plants, such as fruits, and synthetic blends of compoundswhich produce a pleasant taste sensation, such as peppermint and methylsalicylate. Sweetening agents include sucrose, lactose, mannitol,syrups, glycerin, and artificial sweeteners, such as saccharin andaspartame. Suitable emulsifying agents include gelatin, acacia,tragacanth, bentonite, and surfactants, such as polyoxyethylene sorbitanmonooleate (TWEEN® 20), polyoxyethylene sorbitan monooleate 80 (TWEEN®80), and triethanolamine oleate. Suspending and dispersing agentsinclude sodium carboxymethylcellulose, pectin, tragacanth, Veegum,acacia, sodium carbomethylcellulose, hydroxypropyl methylcellulose, andpolyvinylpyrolidone. Preservatives include glycerin, methyl andpropylparaben, benzoic add, sodium benzoate and alcohol. Wetting agentsinclude propylene glycol monostearate, sorbitan monooleate, diethyleneglycol monolaurate, and polyoxyethylene lauryl ether. Solvents includeglycerin, sorbitol, ethyl alcohol, and syrup. Examples of non-aqueousliquids utilized in emulsions include mineral oil and cottonseed oil.Organic acids include citric and tartaric acid. Sources of carbondioxide include sodium bicarbonate and sodium carbonate.

It should be understood that many carriers and excipients may serveseveral functions, even within the same formulation.

The pharmaceutical compositions disclosed herein may be formulated ascompressed tablets, tablet triturates, chewable lozenges, rapidlydissolving tablets, multiple compressed tablets, or enteric-coatingtablets, sugar-coated, or film-coated tablets. Enteric-coated tabletsare compressed tablets coated with substances that resist the action ofstomach acid but dissolve or disintegrate in the intestine, thusprotecting the active ingredients from the acidic environment of thestomach. Enteric-coatings include, but are not limited to, fatty acids,fats, phenylsalicylate, waxes, shellac, ammoniated shellac, andcellulose acetate phthalates. Sugar-coated tablets are compressedtablets surrounded by a sugar coating, which may be beneficial incovering up objectionable tastes or odors and in protecting the tabletsfrom oxidation. Film-coated tablets are compressed tablets that arecovered with a thin layer or film of a water-soluble material. Filmcoatings include, but are not limited to, hydroxyethylcellulose, sodiumcarboxymethylcellulose, polyethylene glycol 4000, and cellulose acetatephthalate. Film coating imparts the same general characteristics assugar coating. Multiple compressed tablets are compressed tablets madeby more than one compression cycle, including layered tablets, andpress-coated or dry-coated tablets.

The tablet dosage forms may be prepared from the active ingredient inpowdered, crystalline, or granular forms, alone or in combination withone or more carriers or excipients described herein, including binders,disintegrants, controlled-release polymers, lubricants, diluents, and/orcolorants. Flavoring and sweetening agents are especially useful in theformation of chewable tablets and lozenges.

The pharmaceutical compositions disclosed herein may be formulated assoft or hard capsules, which can be made from gelatin, methylcellulose,starch, or calcium alginate. The hard gelatin capsule, also known as thedry-filled capsule (DFC), consists of two sections, one slipping overthe other, thus completely enclosing the active ingredient. The softelastic capsule (SEC) is a soft, globular shell, such as a gelatinshell, which is plasticized by the addition of glycerin, sorbitol, or asimilar polyol. The soft gelatin shells may contain a preservative toprevent the growth of microorganisms. Suitable preservatives are thoseas described herein, including methyl- and propyl-parabens, and sorbicacid. The liquid, semisolid, and solid dosage forms disclosed herein maybe encapsulated in a capsule. Suitable liquid and semisolid dosage formsinclude solutions and suspensions in propylene carbonate, vegetableoils, or triglycerides. Capsules containing such solutions can beprepared as described in U.S. Pat. Nos. 4,328,245; 4,409,239; and4,410,545. The capsules may also be coated as known by those of skill inthe art in order to modify or sustain dissolution of the activeingredient.

The pharmaceutical compositions disclosed herein may be formulated inliquid and semisolid dosage forms, including emulsions, solutions,suspensions, elixirs, and syrups. An emulsion is a two-phase system, inwhich one liquid is dispersed in the form of small globules throughoutanother liquid, which can be oil-in-water or water-in-oil. Emulsions mayinclude a pharmaceutically acceptable non-aqueous liquids or solvent,emulsifying agent, and preservative. Suspensions may include apharmaceutically acceptable suspending agent and preservative. Aqueousalcoholic solutions may include a pharmaceutically acceptable acetal,such as a di(lower alkyl) acetal of a lower alkyl aldehyde (the term“lower” means an alkyl having between 1 and 6 carbon atoms), e.g.,acetaldehyde diethyl acetal; and a water-miscible solvent having one ormore hydroxyl groups, such as propylene glycol and ethanol. Elixirs areclear, sweetened, and hydroalcoholic solutions. Syrups are concentratedaqueous solutions of a sugar, for example, sucrose, and may also containa preservative. For a liquid dosage form, for example, a solution in apolyethylene glycol may be diluted with a sufficient quantity of apharmaceutically acceptable liquid carrier, e.g., water, to be measuredconveniently for administration.

Other useful liquid and semisolid dosage forms include, but are notlimited to, those containing the active ingredient(s) disclosed herein,and a dialkylated mono- or poly-alkylene glycol, including,1,2-dimethoxymethane, diglyme, triglyme, tetraglyme, polyethyleneglycol-350-dimethyl ether, polyethylene glycol-550-dimethyl ether,polyethylene glycol-750-dimethyl ether, wherein 350, 550, and 750 referto the approximate average molecular weight of the polyethylene glycol.These formulations may further comprise one or more antioxidants, suchas butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA),propyl gallate, vitamin E, hydroquinone, hydroxycoumarins, ethanolamine,lecithin, cephalin, ascorbic acid, malic acid, sorbitol, phosphoricacid, bisulfite, sodium metabisulfite, thiodipropionic acid and itsesters, and dithiocarbamates.

The pharmaceutical compositions disclosed herein for oral administrationmay be also formulated in the forms of liposomes, micelles,microspheres, or nanosystems. Micellar dosage forms can be prepared asdescribed in U.S. Pat. No. 6,350,458.

The pharmaceutical compositions disclosed herein may be formulated asnon-effervescent or effervescent, granules and powders, to bereconstituted into a liquid dosage form. Pharmaceutically acceptablecarriers and excipients used in the non-effervescent granules or powdersmay include diluents, sweeteners, and wetting agents. Pharmaceuticallyacceptable carriers and excipients used in the effervescent granules orpowders may include organic acids and a source of carbon dioxide.

Coloring and flavoring agents can be used in all of the above dosageforms.

The pharmaceutical compositions disclosed herein may be formulated asimmediate or modified release dosage forms, including delayed-,sustained, pulsed-, controlled, targeted-, and programmed-release forms.

The pharmaceutical compositions disclosed herein may be co-formulatedwith other active ingredients which do not impair the desiredtherapeutic action, or with substances that supplement the desiredaction, such as drotrecogin-a, and hydrocortisone.

B. Parenteral Administration

The pharmaceutical compositions disclosed herein may be administeredparenterally by injection, infusion, or implantation, for local orsystemic administration. Parenteral administration, as used herein,include intravenous, intraarterial, intraperitoneal, intrathecal,intraventricular, intraurethral, intrasternal, intracranial,intramuscular, intrasynovial, and subcutaneous administration.

The pharmaceutical compositions disclosed herein may be formulated inany dosage forms that are suitable for parenteral administration,including solutions, suspensions, emulsions, micelles, liposomes,microspheres, nanosystems, and solid forms suitable for solutions orsuspensions in liquid prior to injection. Such dosage forms can beprepared according to conventional methods known to those skilled in theart of pharmaceutical science (see, Remington: The Science and Practiceof Pharmacy, supra).

The pharmaceutical compositions intended for parenteral administrationmay include one or more pharmaceutically acceptable carriers andexcipients, including, but not limited to, aqueous vehicles,water-miscible vehicles, non-aqueous vehicles, antimicrobial agents orpreservatives against the growth of microorganisms, stabilizers,solubility enhancers, isotonic agents, buffering agents, antioxidants,local anesthetics, suspending and dispersing agents, wetting oremulsifying agents, complexing agents, sequestering or chelating agents,cryoprotectants, lyoprotectants, thickening agents, pH adjusting agents,and inert gases.

Suitable aqueous vehicles include, but are not limited to, water,saline, physiological saline or phosphate buffered saline (PBS), sodiumchloride injection, Ringers injection, isotonic dextrose injection,sterile water injection, dextrose and lactated Ringers injection.Non-aqueous vehicles include, but are not limited to, fixed oils ofvegetable origin, castor oil, corn oil, cottonseed oil, olive oil,peanut oil, peppermint oil, safflower oil, sesame oil, soybean oil,hydrogenated vegetable oils, hydrogenated soybean oil, and medium-chaintriglycerides of coconut oil, and palm seed oil. Water-miscible vehiclesinclude, but are not limited to, ethanol, 1,3-butanediol, liquidpolyethylene glycol (e.g., polyethylene glycol 300 and polyethyleneglycol 400), propylene glycol, glycerin, N-methyl-2-pyrrolidone,dimethylacetamide, and dimethylsulfoxide.

Suitable antimicrobial agents or preservatives include, but are notlimited to, phenols, cresols, mercurials, benzyl alcohol, chlorobutanol,methyl and propyl p-hydroxybenzates, thimerosal, benzalkonium chloride,benzethonium chloride, methyl- and propyl-parabens, and sorbic acid.Suitable isotonic agents include, but are not limited to, sodiumchloride, glycerin, and dextrose. Suitable buffering agents include, butare not limited to, phosphate and citrate. Suitable antioxidants arethose as described herein, including bisulfite and sodium metabisulfite.Suitable local anesthetics include, but are not limited to, procainehydrochloride. Suitable suspending and dispersing agents are those asdescribed herein, including sodium carboxymethylcelluose, hydroxypropylmethylcellulose, and polyvinylpyrrolidone. Suitable emulsifying agentsinclude those described herein, including polyoxyethylene sorbitanmonolaurate, polyoxyethylene sorbitan monooleate 80, and triethanolamineoleate. Suitable sequestering or chelating agents include, but are notlimited to EDTA. Suitable pH adjusting agents include, but are notlimited to, sodium hydroxide, hydrochloric acid, citric acid, and lacticacid. Suitable complexing agents include, but are not limited to,cyclodextrins, including α-cyclodextrin, β-cyclodextrin,hydroxypropyl-β-cyclodextrin, sulfobutylether-β-cyclodextrin, andsulfobutylether 7-β-cyclodextrin (CAPTISOL®, CyDex, Lenexa, Kans.).

The pharmaceutical compositions disclosed herein may be formulated forsingle or multiple dosage administration. The single dosage formulationsare packaged in an ampule, a vial, or a syringe. The multiple dosageparenteral formulations must contain an antimicrobial agent atbacteriostatic or fungistatic concentrations. All parenteralformulations must be sterile, as known and practiced in the art.

In one embodiment, the pharmaceutical compositions are formulated asready-to-use sterile solutions. In another embodiment, thepharmaceutical compositions are formulated as sterile dry solubleproducts, including lyophilized powders and hypodermic tablets, to bereconstituted with a vehicle prior to use. In yet another embodiment,the pharmaceutical compositions are formulated as ready-to-use sterilesuspensions. In yet another embodiment, the pharmaceutical compositionsare formulated as sterile dry insoluble products to be reconstitutedwith a vehicle prior to use. In still another embodiment, thepharmaceutical compositions are formulated as ready-to-use sterileemulsions.

The pharmaceutical compositions disclosed herein may be formulated asimmediate or modified release dosage forms, including delayed-,sustained, pulsed-, controlled, targeted-, and programmed-release forms.

The pharmaceutical compositions may be formulated as a suspension,solid, semi-solid, or thixotropic liquid, for administration as animplanted depot. In one embodiment, the pharmaceutical compositionsdisclosed herein are dispersed in a solid inner matrix, which issurrounded by an outer polymeric membrane that is insoluble in bodyfluids but allows the active ingredient in the pharmaceuticalcompositions diffuse through.

Suitable inner matrixes include polymethylmethacrylate,polybutylmethacrylate, plasticized or unplasticized polyvinylchloride,plasticized nylon, plasticized polyethyleneterephthalate, naturalrubber, polyisoprene, polyisobutylene, polybutadiene, polyethylene,ethylene-vinylacetate copolymers, silicone rubbers,polydimethylsiloxanes, silicone carbonate copolymers, hydrophilicpolymers, such as hydrogels of esters of acrylic and methacrylic acid,collagen, cross-linked polyvinylalcohol, and cross-linked partiallyhydrolyzed polyvinyl acetate.

Suitable outer polymeric membranes include polyethylene, polypropylene,ethylene/propylene copolymers, ethylene/ethyl acrylate copolymers,ethylene/vinylacetate copolymers, silicone rubbers, polydimethylsiloxanes, neoprene rubber, chlorinated polyethylene, polyvinylchloride,vinylchloride copolymers with vinyl acetate, vinylidene chloride,ethylene and propylene, ionomer polyethylene terephthalate, butyl rubberepichlorohydrin rubbers, ethylene/vinyl alcohol copolymer,ethylene/vinyl acetate/vinyl alcohol terpolymer, andethylene/vinyloxyethanol copolymer.

C. Topical Administration

The pharmaceutical compositions disclosed herein may be administeredtopically to the skin, orifices, or mucosa. The topical administration,as used herein, include (intra)dermal, conjuctival, intracorneal,intraocular, ophthalmic, auricular, transdermal, nasal, vaginal,uretheral, respiratory, and rectal administration.

The pharmaceutical compositions disclosed herein may be formulated inany dosage forms that are suitable for topical administration for localor systemic effect, including emulsions, solutions, suspensions, creams,gels, hydrogels, ointments, dusting powders, dressings, elixirs,lotions, suspensions, tinctures, pastes, foams, films, aerosols,irrigations, sprays, suppositories, bandages, dermal patches. Thetopical formulation of the pharmaceutical compositions disclosed hereinmay also comprise liposomes, micelles, microspheres, nanosystems, andmixtures thereof.

Pharmaceutically acceptable carriers and excipients suitable for use inthe topical formulations disclosed herein include, but are not limitedto, aqueous vehicles, water-miscible vehicles, non-aqueous vehicles,antimicrobial agents or preservatives against the growth ofmicroorganisms, stabilizers, solubility enhancers, isotonic agents,buffering agents, antioxidants, local anesthetics, suspending anddispersing agents, wetting or emulsifying agents, complexing agents,sequestering or chelating agents, penetration enhancers,cryopretectants, lyoprotectants, thickening agents, and inert gases.

The pharmaceutical compositions may also be administered topically byelectroporation, iontophoresis, phonophoresis, sonophoresis andmicroneedle or needle-free injection, such as POWDERJECT™ (Chiron Corp.,Emeryville, Calif.), and BIOJECT™ (Bioject Medical Technologies Inc.,Tualatin, Oreg.).

The pharmaceutical compositions disclosed herein may be formulated inthe forms of ointments, creams, and gels. Suitable ointment vehiclesinclude oleaginous or hydrocarbon vehicles, including such as lard,benzoinated lard, olive oil, cottonseed oil, and other oils, whitepetrolatum; emulsifiable or absorption vehicles, such as hydrophilicpetrolatum, hydroxystearin sulfate, and anhydrous lanolin;water-removable vehicles, such as hydrophilic ointment; water-solubleointment vehicles, including polyethylene glycols of varying molecularweight; emulsion vehicles, either water-in-oil (W/O) emulsions oroil-in-water (O/W) emulsions, including cetyl alcohol, glycerylmonostearate, lanolin, and stearic acid (see, Remington: The Science andPractice of Pharmacy, supra). These vehicles are emollient but generallyrequire addition of antioxidants and preservatives.

Suitable cream base can be oil-in-water or water-in-oil. Cream vehiclesmay be water-washable, and contain an oil phase, an emulsifier, and anaqueous phase. The oil phase is also called the “internal” phase, whichis generally comprised of petrolatum and a fatty alcohol such as cetylor stearyl alcohol. The aqueous phase usually, although not necessarily,exceeds the oil phase in volume, and generally contains a humectant. Theemulsifier in a cream formulation may be a nonionic, anionic, cationic,or amphoteric surfactant.

Gels are semisolid, suspension-type systems. Single-phase gels containorganic macromolecules distributed substantially uniformly throughoutthe liquid carrier. Suitable gelling agents include crosslinked acrylicacid polymers, such as carbomers, carboxypolyalkylenes, Carbopol®;hydrophilic polymers, such as polyethylene oxides,polyoxyethylene-polyoxypropylene copolymers, and polyvinylalcohol;cellulosic polymers, such as hydroxypropyl cellulose, hydroxyethylcellulose, hydroxypropyl methylcellulose, hydroxypropyl methylcellulosephthalate, and methylcellulose; gums, such as tragacanth and xanthangum; sodium alginate; and gelatin. In order to prepare a uniform gel,dispersing agents such as alcohol or glycerin can be added, or thegelling agent can be dispersed by trituration, mechanical mixing, and/orstirring.

The pharmaceutical compositions disclosed herein may be administeredrectally, urethrally, vaginally, or perivaginally in the forms ofsuppositories, pessaries, bougies, poultices or cataplasm, pastes,powders, dressings, creams, plasters, contraceptives, ointments,solutions, emulsions, suspensions, tampons, gels, foams, sprays, orenemas. These dosage forms can be manufactured using conventionalprocesses as described in Remington: The Science and Practice ofPharmacy, supra.

Rectal, urethral, and vaginal suppositories are solid bodies forinsertion into body orifices, which are solid at ordinary temperaturesbut melt or soften at body temperature to release the activeingredient(s) inside the orifices. Pharmaceutically acceptable carriersutilized in rectal and vaginal suppositories include bases or vehicles,such as stiffening agents, which produce a melting point in theproximity of body temperature, when formulated with the pharmaceuticalcompositions disclosed herein; and antioxidants as described herein,including bisulfite and sodium metabisulfite. Suitable vehicles include,but are not limited to, cocoa butter (theobroma oil), glycerin-gelatin,carbowax (polyoxyethylene glycol), spermaceti, paraffin, white andyellow wax, and appropriate mixtures of mono-, di- and triglycerides offatty acids, hydrogels, such as polyvinyl alcohol, hydroxyethylmethacrylate, polyacrylic acid; glycerinated gelatin. Combinations ofthe various vehicles may be used. Rectal and vaginal suppositories maybe prepared by the compressed method or molding. The typical weight of arectal and vaginal suppository is about 2 to about 3 g.

The pharmaceutical compositions disclosed herein may be administeredophthalmically in the forms of solutions, suspensions, ointments,emulsions, gel-forming solutions, powders for solutions, gels, ocularinserts, and implants.

The pharmaceutical compositions disclosed herein may be administeredintranasally or by inhalation to the respiratory tract. Thepharmaceutical compositions may be formulated in the form of an aerosolor solution for delivery using a pressurized container, pump, spray,atomizer, such as an atomizer using electrohydrodynamics to produce afine mist, or nebulizer, alone or in combination with a suitablepropellant, such as 1,1,1,2-tetrafluoroethane or1,1,1,2,3,3,3-heptafluoropropane. The pharmaceutical compositions mayalso be formulated as a dry powder for insufflation, alone or incombination with an inert carrier such as lactose or phospholipids; andnasal drops. For intranasal use, the powder may comprise a bioadhesiveagent, including chitosan or cyclodextrin.

Solutions or suspensions for use in a pressurized container, pump,spray, atomizer, or nebulizer may be formulated to contain ethanol,aqueous ethanol, or a suitable alternative agent for dispersing,solubilizing, or extending release of the active ingredient disclosedherein, a propellant as solvent; and/or an surfactant, such as sorbitantrioleate, oleic acid, or an oligolactic acid.

The pharmaceutical compositions disclosed herein may be micronized to asize suitable for delivery by inhalation, such as about 50 micrometersor less, or about 10 micrometers or less. Particles of such sizes may beprepared using a comminuting method known to those skilled in the art,such as spiral jet milling, fluid bed jet milling, supercritical fluidprocessing to form nanoparticles, high pressure homogenization, or spraydrying.

Capsules, blisters and cartridges for use in an inhaler or insufflatormay be formulated to contain a powder mix of the pharmaceuticalcompositions disclosed herein; a suitable powder base, such as lactoseor starch; and a performance modifier, such as l-leucine, mannitol, ormagnesium stearate. The lactose may be anhydrous or in the form of themonohydrate. Other suitable excipients or carriers include dextran,glucose, maltose, sorbitol, xylitol, fructose, sucrose, and trehalose.The pharmaceutical compositions disclosed herein for inhaled/intranasaladministration may further comprise a suitable flavor, such as mentholand levomenthol, or sweeteners, such as saccharin or saccharin sodium.

The pharmaceutical compositions disclosed herein for topicaladministration may be formulated to be immediate release or modifiedrelease, including delayed-, sustained-, pulsed-, controlled-, targeted,and programmed release.

D. Modified Release

The pharmaceutical compositions disclosed herein may be formulated as amodified release dosage form. As used herein, the term “modifiedrelease” refers to a dosage form in which the rate or place of releaseof the active ingredient(s) is different from that of an immediatedosage form when administered by the same route. Modified release dosageforms include delayed-, extended-, prolonged-, sustained-, pulsatile-,controlled-, accelerated- and fast-, targeted-, programmed-release, andgastric retention dosage forms. The pharmaceutical compositions inmodified release dosage forms can be prepared using a variety ofmodified release devices and methods known to those skilled in the art,including, but not limited to, matrix controlled release devices,osmotic controlled release devices, multiparticulate controlled releasedevices, ion-exchange resins, enteric coatings, multilayered coatings,microspheres, liposomes, and combinations thereof. The release rate ofthe active ingredient(s) can also be modified by varying the particlesizes and polymorphorism of the active ingredient(s).

Examples of modified release include, but are not limited to, thosedescribed in U.S. Pat. Nos. 3,845,770; 3,916,899; 3,536,809; 3,598,123;4,008,719; 5,674,533; 5,059,595; 5,591,767; 5,120,548; 5,073,543;5,639,476; 5,354,556; 5,639,480; 5,733,566; 5,739,108; 5,891,474;5,922,356; 5,972,891; 5,980,945; 5,993,855; 6,045,830; 6,087,324;6,113,943; 6,197,350; 6,248,363; 6,264,970; 6,267,981; 6,376,461;6,419,961; 6,589,548; 6,613,358; and 6,699,500.

1. Matrix Controlled Release Devices

The pharmaceutical compositions disclosed herein in a modified releasedosage form may be fabricated using a matrix controlled release deviceknown to those skilled in the art (see, Takada et al in “Encyclopedia ofControlled Drug Delivery,” Vol. 2, Mathiowitz ed., Wiley, 1999).

In one embodiment, the pharmaceutical compositions disclosed herein in amodified release dosage form is formulated using an erodible matrixdevice, which is water-swellable, erodible, or soluble polymers,including synthetic polymers, and naturally occurring polymers andderivatives, such as polysaccharides and proteins.

Materials useful in forming an erodible matrix include, but are notlimited to, chitin, chitosan, dextran, and pullulan; gum agar, gumarabic, gum karaya, locust bean gum, gum tragacanth, carrageenans, gumghatti, guar gum, xanthan gum, and scleroglucan; starches, such asdextrin and maltodextrin; hydrophilic colloids, such as pectin;phosphatides, such as lecithin; alginates; propylene glycol alginate;gelatin; collagen; and cellulosics, such as ethyl cellulose (EC),methylethyl cellulose (MEC), carboxymethyl cellulose (CMC), CMEC,hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), celluloseacetate (CA), cellulose propionate (CP), cellulose butyrate (CB),cellulose acetate butyrate (CAB), CAP, CAT, hydroxypropyl methylcellulose (HPMC), HPMCP, HPMCAS, hydroxypropyl methyl cellulose acetatetrimellitate (HPMCAT), and ethylhydroxy ethylcellulose (EHEC); polyvinylpyrrolidone; polyvinyl alcohol; polyvinyl acetate; glycerol fatty acidesters; polyacrylamide; polyacrylic acid; copolymers of ethacrylic acidor methacrylic acid (EUDRAGIT®, Rohm America, Inc., Piscataway, N.J.);poly(2-hydroxyethyl-methacrylate); polylactides; copolymers ofL-glutamic acid and ethyl-L-glutamate; degradable lactic acid-glycolicacid copolymers; poly-D-(−)-3-hydroxybutyric acid; and other acrylicacid derivatives, such as homopolymers and copolymers ofbutylmethacrylate, methylmethacrylate, ethylmethacrylate, ethylacrylate,(2-dimethylaminoethyl)methacrylate, and(trimethylaminoethyl)methacrylate chloride.

In further embodiments, the pharmaceutical compositions are formulatedwith a non-erodible matrix device. The active ingredient(s) is dissolvedor dispersed in an inert matrix and is released primarily by diffusionthrough the inert matrix once administered. Materials suitable for useas a non-erodible matrix device included, but are not limited to,insoluble plastics, such as polyethylene, polypropylene, polyisoprene,polyisobutylene, polybutadiene, polymethylmethacrylate,polybutylmethacrylate, chlorinated polyethylene, polyvinylchloride,methyl acrylate-methyl methacrylate copolymers, ethylene-vinylacetatecopolymers, ethylene/propylene copolymers, ethylene/ethyl acrylatecopolymers, vinylchloride copolymers with vinyl acetate, vinylidenechloride, ethylene and propylene, ionomer polyethylene terephthalate,butyl rubber epichlorohydrin rubbers, ethylene/vinyl alcohol copolymer,ethylene/vinyl acetate/vinyl alcohol terpolymer, andethylene/vinyloxyethanol copolymer, polyvinyl chloride, plasticizednylon, plasticized polyethyleneterephthalate, natural rubber, siliconerubbers, polydimethylsiloxanes, silicone carbonate copolymers;hydrophilic polymers, such as ethyl cellulose, cellulose acetate,crospovidone, and cross-linked partially hydrolyzed polyvinyl acetate;and fatty compounds, such as carnauba wax, microcrystalline wax, andtriglycerides.

In a matrix controlled release system, the desired release kinetics canbe controlled, for example, via the polymer type employed, the polymerviscosity, the particle sizes of the polymer and/or the activeingredient(s), the ratio of the active ingredient(s) versus the polymer,and other excipients or carriers in the compositions.

The pharmaceutical compositions disclosed herein in a modified releasedosage form may be prepared by methods known to those skilled in theart, including direct compression, dry or wet granulation followed bycompression, melt-granulation followed by compression.

2. Osmotic Controlled Release Devices

The pharmaceutical compositions disclosed herein in a modified releasedosage form may be fabricated using an osmotic controlled releasedevice, including one-chamber system, two-chamber system, asymmetricmembrane technology (AMT), and extruding core system (ECS). In general,such devices have at least two components: (a) the core which containsthe active ingredient(s) and (b) a semipermeable membrane with at leastone delivery port, which encapsulates the core. The semipermeablemembrane controls the influx of water to the core from an aqueousenvironment of use so as to cause drug release by extrusion through thedelivery port(s).

In addition to the active ingredient(s), the core of the osmotic deviceoptionally includes an osmotic agent, which creates a driving force fortransport of water from the environment of use into the core of thedevice. One class of osmotic agents water-swellable hydrophilicpolymers, which are also referred to as “osmopolymers” and “hydrogels,”including, but not limited to, hydrophilic vinyl and acrylic polymers,polysaccharides such as calcium alginate, polyethylene oxide (PEO),polyethylene glycol (PEG), polypropylene glycol (PPG),poly(2-hydroxyethyl methacrylate), poly(acrylic) acid, poly(methacrylic)acid, polyvinylpyrrolidone (PVP), crosslinked PVP, polyvinyl alcohol(PVA), PVA/PVP copolymers, PVA/PVP copolymers with hydrophobic monomerssuch as methyl methacrylate and vinyl acetate, hydrophilic polyurethanescontaining large PEO blocks, sodium croscarmellose, carrageenan,hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC),hydroxypropyl methyl cellulose (HPMC), carboxymethyl cellulose (CMC) andcarboxyethyl, cellulose (CEC), sodium alginate, polycarbophil, gelatin,xanthan gum, and sodium starch glycolate.

The other class of osmotic agents are osmogens, which are capable ofimbibing water to affect an osmotic pressure gradient across the barrierof the surrounding coating. Suitable osmogens include, but are notlimited to, inorganic salts, such as magnesium sulfate, magnesiumchloride, calcium chloride, sodium chloride, lithium chloride, potassiumsulfate, potassium phosphates, sodium carbonate, sodium sulfite, lithiumsulfate, potassium chloride, and sodium sulfate; sugars, such asdextrose, fructose, glucose, inositol, lactose, maltose, mannitol,raffinose, sorbitol, sucrose, trehalose, and xylitol; organic acids,such as ascorbic acid, benzoic acid, fumaric acid, citric acid, maleicacid, sebacic acid, sorbic acid, adipic acid, edetic acid, glutamicacid, p-tolunesulfonic acid, succinic acid, and tartaric acid; urea; andmixtures thereof.

Osmotic agents of different dissolution rates may be employed toinfluence how rapidly the active ingredient(s) is initially deliveredfrom the dosage form. For example, amorphous sugars, such as MannogemeEZ (SPI Pharma, Lewes, Del.) can be used to provide faster deliveryduring the first couple of hours to promptly produce the desiredtherapeutic effect, and gradually and continually release of theremaining amount to maintain the desired level of therapeutic orprophylactic effect over an extended period of time. In this case, theactive ingredient(s) is released at such a rate to replace the amount ofthe active ingredient metabolized and excreted.

The core may also include a wide variety of other excipients andcarriers as described herein to enhance the performance of the dosageform or to promote stability or processing.

Materials useful in forming the semipermeable membrane include variousgrades of acrylics, vinyls, ethers, polyamides, polyesters, andcellulosic derivatives that are water-permeable and water-insoluble atphysiologically relevant pHs, or are susceptible to being renderedwater-insoluble by chemical alteration, such as crosslinking. Examplesof suitable polymers useful in forming the coating, include plasticized,unplasticized, and reinforced cellulose acetate (CA), cellulosediacetate, cellulose triacetate, CA propionate, cellulose nitrate,cellulose acetate butyrate (CAB), CA ethyl carbamate, CAP, CA methylcarbamate, CA succinate, cellulose acetate trimellitate (CAT), CAdimethylaminoacetate, CA ethyl carbonate, CA chloroacetate, CA ethyloxalate, CA methyl sulfonate, CA butyl sulfonate, CA p-toluenesulfonate, agar acetate, amylose triacetate, beta glucan acetate, betaglucan triacetate, acetaldehyde dimethyl acetate, triacetate of locustbean gum, hydroxlated ethylene-vinylacetate, EC, PEG, PPG, PEG/PPGcopolymers, PVP, HEC, HPC, CMC, CMEC, HPMC, HPMCP, HPMCAS, HPMCAT,poly(acrylic) acids and esters and poly-(methacrylic) acids and estersand copolymers thereof, starch, dextran, dextrin, chitosan, collagen,gelatin, polyalkenes, polyethers, polysulfones, polyethersulfones,polystyrenes, polyvinyl halides, polyvinyl esters and ethers, naturalwaxes, and synthetic waxes.

Semipermeable membrane may also be a hydrophobic microporous membrane,wherein the pores are substantially filled with a gas and are not wettedby the aqueous medium but are permeable to water vapor, as disclosed inU.S. Pat. No. 5,798,119. Such hydrophobic but water-vapor permeablemembrane are typically composed of hydrophobic polymers such aspolyalkenes, polyethylene, polypropylene, polytetrafluoroethylene,polyacrylic acid derivatives, polyethers, polysulfones,polyethersulfones, polystyrenes, polyvinyl halides, polyvinylidenefluoride, polyvinyl esters and ethers, natural waxes, and syntheticwaxes.

The delivery port(s) on the semipermeable membrane may be formedpost-coating by mechanical or laser drilling. Delivery port(s) may alsobe formed in situ by erosion of a plug of water-soluble material or byrupture of a thinner portion of the membrane over an indentation in thecore. In addition, delivery ports may be formed during coating process,as in the case of asymmetric membrane coatings of the type disclosed inU.S. Pat. Nos. 5,612,059 and 5,698,220.

The total amount of the active ingredient(s) released and the releaserate can substantially by modulated via the thickness and porosity ofthe semipermeable membrane, the composition of the core, and the number,size, and position of the delivery ports.

The pharmaceutical compositions in an osmotic controlled-release dosageform may further comprise additional conventional excipients or carriersas described herein to promote performance or processing of theformulation.

The osmotic controlled-release dosage forms can be prepared according toconventional methods and techniques known to those skilled in the art(see, Remington: The Science and Practice of Pharmacy, supra; Santus andBaker, J. Controlled Release 1995, 35, 1-21; Verma et al., DrugDevelopment and Industrial Pharmacy 2000, 26, 695-708; Verma et al., J.Controlled Release 2002, 79, 7-27).

In certain embodiments, the pharmaceutical compositions disclosed hereinare formulated as AMT controlled-release dosage form, which comprises anasymmetric osmotic membrane that coats a core comprising the activeingredient(s) and other pharmaceutically acceptable excipients orcarriers. See, U.S. Pat. No. 5,612,059 and WO 2002/17918. The AMTcontrolled-release dosage forms can be prepared according toconventional methods and techniques known to those skilled in the art,including direct compression, dry granulation, wet granulation, and adip-coating method.

In certain embodiments, the pharmaceutical compositions disclosed hereinare formulated as ESC controlled-release dosage form, which comprises anosmotic membrane that coats a core comprising the active ingredient(s),a hydroxylethyl cellulose, and other pharmaceutically acceptableexcipients or carriers.

3. Multiparticulate Controlled Release Devices

The pharmaceutical compositions disclosed herein in a modified releasedosage form may be fabricated a multiparticulate controlled releasedevice, which comprises a multiplicity of particles, granules, orpellets, ranging from about 10 μm to about 3 mm, about 50 μm to about2.5 mm, or from about 100 μm to about 1 mm in diameter. Suchmultiparticulates may be made by the processes know to those skilled inthe art, including wet-and dry-granulation, extrusion/spheronization,roller-compaction, melt-congealing, and by spray-coating seed cores.See, for example, Multiparticulate Oral Drug Delivery; Marcel Dekker:1994; and Pharmaceutical Pelletization Technology; Marcel Dekker: 1989.

Other excipients or carriers as described herein may be blended with thepharmaceutical compositions to aid in processing and forming themultiparticulates. The resulting particles may themselves constitute themultiparticulate device or may be coated by various film-formingmaterials, such as enteric polymers, water-swellable, and water-solublepolymers. The multiparticulates can be further processed as a capsule ora tablet.

4. Targeted Delivery

The pharmaceutical compositions disclosed herein may also be formulatedto be targeted to a particular tissue, receptor, or other area of thebody of the subject to be treated, including liposome-, resealederythrocyte-, and antibody-based delivery systems. Examples include, butare not limited to, U.S. Pat. Nos. 6,316,652; 6,274,552; 6,271,359;6,253,872; 6,139,865; 6,131,570; 6,120,751; 6,071,495; 6,060,082;6,048,736; 6,039,975; 6,004,534; 5,985,307; 5,972,366; 5,900,252;5,840,674; 5,759,542; and 5,709,874.

Methods of Use

Disclosed are methods for treating, preventing, or ameliorating one ormore symptoms of an NMDA receptor mediated-disorder, comprisingadministering to a subject having or being suspected to have such adisorder, a therapeutically effective amount of a compound as disclosedherein; or a pharmaceutically acceptable salt, solvate, or prodrugthereof.

NMDA receptor mediated-disorders include, but are not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors.

Also disclosed are methods of treating, preventing, or ameliorating oneor more symptoms of a disorder associated with NMDA receptors, byadministering to a subject having or being suspected to have such adisorder, a therapeutically effective amount of a compound as disclosedherein; or a pharmaceutically acceptable salt, solvate, or prodrugthereof.

Further disclosed are methods of treating, preventing, or amelioratingone or more symptoms of a disorder responsive to modulation of NMDAreceptors, comprising administering to a subject having or beingsuspected to have such a disorder, a therapeutically effective amount ofa compound as disclosed herein; or a pharmaceutically acceptable salt,solvate, or prodrug thereof.

Furthermore, disclosed herein are methods of modulating the activity ofNMDA receptors, comprising contacting the receptors with at least onecompound as disclosed herein; or a pharmaceutically acceptable salt,solvate, or prodrug thereof. In one embodiment, the NMDA receptor(s) areexpressed by a cell.

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein; or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to affect decreasedinter-individual variation in plasma levels of the compound or ametabolite thereof, during the treatment of the disorder as compared tothe corresponding non-isotopically enriched compound.

In certain embodiments, the inter-individual variation in plasma levelsof the compounds as disclosed herein, or metabolites thereof, isdecreased by greater than about 5%, greater than about 10%, greater thanabout 20%, greater than about 300%, greater than about 40%, or bygreater than about 50% as compared to the corresponding non-isotopicallyenriched compound.

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein; or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to affect increasedaverage plasma levels of the compound or decreased average plasma levelsof at least one metabolite of the compound per dosage unit as comparedto the corresponding non-isotopically enriched compound.

In certain embodiments, the average plasma levels of the compound asdisclosed herein are increased by greater than about 5%, greater thanabout 10%, greater than about 20%, greater than about 30%, greater thanabout 40%, or greater than about 50% as compared to the correspondingnon-isotopically enriched compounds.

In certain embodiments, the average plasma levels of a metabolite of thecompound as disclosed herein are decreased by greater than about 5%,greater than about 10%, greater than about 20%, greater than about 30%,greater than about 40%, or greater than about 50% as compared to thecorresponding non-isotopically enriched compounds

Plasma levels of the compound as disclosed herein, or metabolitesthereof, are measured using the methods described by Li et al. (RapidCommunications in Mass Spectrometry 2005, 19, 1943-1950).

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein, or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to affect adecreased inhibition of, and/or metabolism by at least one cytochromeP₄₅₀ or monoamine oxidase isoform in the subject during the treatment ofthe disease as compared to the corresponding non-isotopically enrichedcompound.

Examples of cytochrome P₄₅₀ isoforms in a mammalian subject include, butare not limited to, CYP1A1, CYP1A2, CYP1B1, CYP2A6, CYP2A13, CYP2B6,CYP2C8, CYP2C9, CYP2C18, CYP2C19, CYP2D6, CYP2E1, CYP2G1, CYP2J2,CYP2R1, CYP2S1, CYP3A4, CYP3A5, CYP3A5P1, CYP3A5P2, CYP3A7, CYP4A11,CYP4B1, CYP4F2, CYP4F3, CYP4F8, CYP4F11, CYP4F12, CYP4X1, CYP4Z1,CYP5A1, CYP7A1, CYP7B1, CYP8A1, CYP8B1, CYP11A1, CYP11B1, CYP11B2,CYP17, CYP19, CYP21, CYP24, CYP26A1, CYP26B1, CYP27A1, CYP27B1, CYP39,CYP46, and CYP51.

Examples of monoamine oxidase isoforms in a mammalian subject include,but are not limited to, MAO_(A), and MAO_(B).

In certain embodiments, the decrease in inhibition of the cytochromeP₄₅₀ or monoamine oxidase isoform by a compound as disclosed herein isgreater than about 5%, greater than about 10%, greater than about 20%,greater than about 30%, greater than about 40%, or greater than about50% as compared to the corresponding non-isotopically enrichedcompounds.

The inhibition of the cytochrome P₄₅₀ isoform is measured by the methodof Ko et al. (British Journal of Clinical Pharmacology, 2000, 49,343-351). The inhibition of the MAO_(A) isoform is measured by themethod of Weyler et al. (J. Biol Chem. 1985, 260, 13199-13207). Theinhibition of the MAO_(B) isoform is measured by the method of Uebelhacket al. (Pharmacopsychiatry, 1998, 31, 187-192).

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein, or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to affect adecreased metabolism via at least one polymorphically-expressedcytochrome P₄₅₀ isoform in the subject during the treatment of thedisorder as compared to the corresponding non-isotopically enrichedcompound.

Examples of polymorphically-expressed cytochrome P₄₅₀ isoforms in amammalian subject include, but are not limited to, CYP2C8, CYP2C9,CYP2C19, and CYP2D6.

In certain embodiments, the decrease in metabolism of the compound asdisclosed herein by at least one polymorphically-expressed cytochromeP₄₅₀ isoforms cytochrome P₄₅₀ isoform is greater than about 5%, greaterthan about 10%, greater than about 20%, greater than about 30%, greaterthan about 40%, or greater than about 50% as compared to thecorresponding non-isotopically enriched compound.

The metabolic activities of the cytochrome P₄₅₀ isoforms are measured bythe method described in Example 5. The metabolic activities of themonoamine oxidase isoforms are measured by the methods described inExamples 6, and 7.

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein, or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to affect at leastone statistically-significantly improved disorder-control and/ordisorder-eradication endpoint, as compared to the correspondingnon-isotopically enriched compound.

Examples of improved disorder-control and/or diorder-eradicationendpoints include, but are not limited to, statistically-significantimprovement of pain indices, perfusion of ischemic tissues with oxygen,prevention of ischemia, entheogenic effects sufficient to facilitatepsychotherapy, cataleptic effects sufficient to enable medical treatmentof a non-compliant trauma victim, neuroprotection during an ischemicevent, and/or diminution of hepatotoxicity, as compared to thecorresponding non-isotopically enriched compound.

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein, or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to affect animproved clinical effect as compared to the correspondingnon-isotopically enriched compound. Examples of improved clinicaleffects include, but are not limited to, statistically-significantimprovement of pain indices, perfusion of ischemic tissues with oxygen,prevention of ischemia, entheogenic effects sufficient to facilitatepsychotherapy, cataleptic effects sufficient to enable medical treatmentof a non-compliant trauma victim, neuroprotection during an ischemicevent, and/or diminution of hepatotoxicity, as compared to thecorresponding non-isotopically enriched compound.

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein, or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to affect preventionof recurrence, or delay of decline or appearance, of abnormal alimentaryor hepatic parameters as the primary clinical benefit, as compared tothe corresponding non-isotopically enriched compound.

Disclosed herein are methods for treating a subject, including a human,having or suspected of having a disorder involving, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors, or forpreventing such a disorder in a subject prone to the disorder;comprising administering to the subject a therapeutically effectiveamount of a compound as disclosed herein, or a pharmaceuticallyacceptable salt, solvate, or prodrug thereof; so as to allow thetreatment of, but not limited to, nociceptive pain, neuropathic pain,phantom limb pain, ischemic pain, stroke, sepsis, inflammation, opioidtolerance, Alzheimer's disease, burn, any disorder which can lessened,alleviated, or benefited by administering an anesthetic, analgesic,entheogen, therapeutic cataleptic, or neuroprotective agent, and/or anydisorder which can lessened, alleviated, or benefited by modulating NMDAreceptors while reducing or eliminating deleterious changes in anydiagnostic hepatobiliary function endpoints as compared to thecorresponding non-isotopically enriched compound.

Examples of diagnostic hepatobiliary function endpoints include, but arenot limited to, alanine aminotransferase (“ALT”), serum glutamic-pyruvictransaminase (“SGPT”), aspartate aminotransferase (“AST” or “SGOT”),ALT/AST ratios, serum aldolase, alkaline phosphatase (“ALP”), ammonialevels, bilirubin, gamma-glutamyl transpeptidase (“GGTP,” “

-GTP,” or “GGT”), leucine aminopeptidase (“LAP”), liver biopsy, liverultrasonography, liver nuclear scan, 5′-nucleotidase, and blood protein.Hepatobiliary endpoints are compared to the stated normal levels asgiven in “Diagnostic and Laboratory Test Reference”, 4^(th) edition,Mosby, 1999. These assays are run by accredited laboratories accordingto standard protocol.

Depending on the disease to be treated and the subject's condition, thecompound as disclosed herein disclosed herein may be administered byoral, parenteral (e.g., intramuscular, intraperitoneal, intravenous,ICV, intracistemal injection or infusion, subcutaneous injection, orimplant), inhalation, nasal, vaginal, rectal, sublingual, or topical(e.g., transdermal or local) routes of administration, and may beformulated, alone or together, in suitable dosage unit withpharmaceutically acceptable carriers, adjuvants and vehicles appropriatefor each route of administration.

The dose may be in the form of one, two, three, four, five, six, or moresub-doses that are administered at appropriate intervals per day. Thedose or sub-doses can be administered in the form of dosage unitscontaining from about 0.1 to about 1000 milligram, from about 0.1 toabout 500 milligrams, or from 0.5 about to about 100 milligram activeingredient(s) per dosage unit, and if the condition of the patientrequires, the dose can, by way of alternative, be administered as acontinuous infusion.

In certain embodiments, an appropriate dosage level is about 0.01 toabout 100 mg per kg patient body weight per day (mg/kg per day), about0.01 to about 50 mg/kg per day, about 0.01 to about 25 mg/kg per day, orabout 0.05 to about 10 mg/kg per day, which may be administered insingle or multiple doses. A suitable dosage level may be about 0.01 toabout 100 mg/kg per day, about 0.05 to about 50 mg/kg per day, or about0.1 to about 10 mg/kg per day. Within this range the dosage may be about0.01 to about 0.1, about 0.1 to about 1.0, about 1.0 to about 10, orabout 10 to about 50 mg/kg per day.

Combination Therapy

The compounds disclosed herein may also be combined or used incombination with other agents useful in the treatment, prevention, oramelioration of one or more symptoms of the disorders for which thecompound disclosed herein are useful, including, but not limited to,nociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease,burn, any disorder which can lessened, alleviated, or benefited byadministering an anesthetic, analgesic, entheogen, therapeuticcataleptic, or neuroprotective agent, and/or any disorder which canlessened, alleviated, or benefited by modulating NMDA receptors. Or, byway of example only, the therapeutic effectiveness of one of thecompounds described herein may be enhanced by administration of anadjuvant (i.e., by itself the adjuvant may only have minimal therapeuticbenefit, but in combination with another therapeutic agent, the overalltherapeutic benefit to the patient is enhanced).

Such other agents, adjuvants, or drugs, may be administered, by a routeand in an amount commonly used therefor, simultaneously or sequentiallywith a compound as disclosed herein. When a compound as disclosed hereindisclosed herein is used contemporaneously with one or more other drugs,a pharmaceutical composition containing such other drugs in addition tothe compound disclosed herein may be utilized, but is not required.Accordingly, the pharmaceutical compositions disclosed herein includethose that also contain one or more other active ingredients ortherapeutic agents, in addition to the compound disclosed herein.

In certain embodiments, the compounds disclosed herein can be combinedwith one or more modulators of NMDA-receptors known in the art,including, but not limited to, phencyclidine (PCP), amantadine,ibogaine, memantine, nitrous oxide, and dextromethorphan.

In certain embodiments, the compounds disclosed herein can be combinedwith one or more natural, semisynthetic, or fully synthetic opioidsknown in the art, including, but not limited to, morphine, codeine,thebain, diacetylmorphine, oxycodone, hydrocodone, hydromorphone,oxymorphone, nicomorphine, fentanyl, α-methylfentanyl, alfentanil,sufentanil, remifentanyl, carfentanyl, ohmefentanyl, pethidine,ketobemidone, propoxyphene, dextropropoxyphene, methadone, loperamide,pentazocine, buprenorphine, etorphine, butorphanol, nalbutine,levorphanol, naloxone, naltrexone, and tramadol.

In certain embodiments, the compounds provided herein can be combinedwith one or more local or general anesthetics known in the art,including, but not limited to, diethyl ether, vinyl ether, halothane,chloroform, methoxyflurane, enflurane, trichloroethylene, isoflurane,desflurane, sevoflurane, methohexital, hexobarbital, thiopental,narcobarbital, fentanyl, alfentanil, sufentanil, phenoperidine,anileridine, remifentanil, droperidol, ketamine, propanidid, alfaxalone,etomidate, propofol, hydroxybutyric acid, nitrous oxide, esketamine,metabutethamine, procaine, tetracaine, chloroprocaine, benzocaine,bupivacaine, lidocaine, mepivacaine, prilocaine, butanilicaine,cinchocaine, etidocaine, articaine, ropivacaine, levobupivacaine,cocaine, ethyl chloride, dyclonine, phenol, and capsaicin.

In certain embodiments, the compounds disclosed herein can be combinedwith one or more peripherally acting muscle relaxants known in the art,including, but not limited to alcuronium, dimethyltubocurarine,tubocurarine, suxamethonium, atracurium, cisatracurium, doxacuriumchloride, fazadinium bromide, gallamine, hexafluronium, mivacuriumchloride, pancuronium, pipecuronium bromide, rocuronium bromide,vecuronium, and botulinum toxin.

In certain embodiments, the compounds disclosed herein can be combinedwith one or more benzodiazepines (“minor tranquilizers”) known in theart, including, but not limited to alprazolam, bromazepam, clonazepam,diazepam, estazolam, flunitrazepam, lorazepam, midazolam, nitrazepam,oxazepam, triazolam, temazepam, and chlordiazepoxide.

The compounds disclosed herein can also be administered in combinationwith other classes of compounds, including, but not limited to,endothelin converting enzyme (ECE) inhibitors, such as phosphoramidon;thromboxane receptor antagonists, such as ifetroban; potassium channelopeners; thrombin inhibitors, such as hirudin; growth factor inhibitors,such as modulators of PDGF activity; platelet activating factor (PAF)antagonists; anti-platelet agents, such as GPIIb/IIa blockers (e.g.,abdximab, eptifibatide, and tirofiban), P2Y(AC) antagonists (e.g.,clopidogrel, ticlopidine and CS-747), and aspirin; anticoagulants, suchas warfarin; low molecular weight heparins, such as enoxaparin; FactorVIIa Inhibitors and Factor Xa Inhibitors; renin inhibitors; neutralendopeptidase (NEP) inhibitors; vasopepsidase inhibitors (dual NEP-ACEinhibitors), such as omapatrilat and gemopatrilat; HMG CoA reductaseinhibitors, such as pravastatin, lovastatin, atorvastatin, simvastatin,NK-104 (a.k.a. itavastatin, nisvastatin, or nisbastatin), and ZD-4522(also known as rosuvastatin, or atavastatin or visastatin); squalenesynthetase inhibitors; fibrates; bile acid sequestrants, such asquestran; niacin; anti-atherosclerotic agents, such as ACAT inhibitors;MTP Inhibitors; calcium channel blockers, such as amlodipine besylate;potassium channel activators; alpha-adrenergic agents; beta-adrenergicagents, such as carvedilol and metoprolol; antiarrhythmic agents;diuretics, such as chlorothlazide, hydrochlorothiazide, flumethiazide,hydroflumethiazide, bendroflumethiazide, methylchlorothiazide,trichloromethiazide, polythiazide, benzothiazide, ethacrynic acid,tricrynafen, chlorthalidone, furosenilde, musolimine, bumetanide,triamterene, amiloride, and spironolactone; thrombolytic agents, such astissue plasminogen activator (tPA), recombinant tPA, streptokinase,urokinase, prourokinase, and anisoylated plasminogen streptokinaseactivator complex (APSAC); anti-diabetic agents, such as biguanides(e.g. metformin), glucosidase inhibitors (e.g., acarbose), insulins,meglitinides (e.g., repaglinide), sulfonylureas (e.g., glimepiride,glyburide, and glipizide), thiozolidinediones (e.g. troglitazone,rosiglitazone and pioglitazone), and PPAR-gamma agonists;mineralocorticoid receptor antagonists, such as spironolactone andeplerenone; growth hormone secretagogues; aP2 inhibitors;phosphodiesterase inhibitors, such as PDE III inhibitors (e.g.,cilostazol) and PDE V inhibitors (e.g., sildenafil, tadalafil,vardenafil); protein tyrosine kinase inhibitors; antiinflammatories;antiproliferatives, such as methotrexate, FK506 (tacrolimus, Prograf),mycophenolate mofetil; chemotherapeutic agents; immunosuppressants;anticancer agents and cytotoxic agents (e.g., alkylating agents, such asnitrogen mustards, alkyl sulfonates, nitrosoureas, ethylenimines, andtriazenes); antimetabolites, such as folate antagonists, purineanalogues, and pyrridine analogues; antibiotics, such as anthracyclines,bleomycins, mitomycin, dactinomycin, and plicamycin; enzymes, such asL-asparaginase; farnesyl-protein transferase inhibitors; hormonalagents, such as glucocorticoids (e.g., cortisone),estrogens/antiestrogens, androgens/antiandrogens, progestins, andluteinizing hormone-releasing hormone anatagonists, and octreotideacetate; microtubule-disruptor agents, such as ecteinascidins;microtubule-stablizing agents, such as pacitaxel, docetaxel, andepothilones A-F; plant-derived products, such as vinca alkaloids,epipodophyllotoxins, and taxanes; and topoisomerase inhibitors;prenyl-protein transferase inhibitors; and cyclosporins; steroids, suchas prednisone and dexamethasone; cytotoxic drugs, such as azathiprineand cyclophosphamide; TNF-alpha inhibitors, such as tenidap; anti-TNFantibodies or soluble TNF receptor, such as etanercept, rapamycin, andleflunimide; and cyclooxygenase-2 (COX-2) inhibitors, such as celecoxiband rofecoxib; and miscellaneous agents such as, hydroxyurea,procarbazine, mitotane, hexamethylmelamine, gold compounds, platinumcoordination complexes, such as cisplatin, satraplatin, and carboplatin.

Kits/Articles of Manufacture

For use in the therapeutic applications described herein, kits andarticles of manufacture are also described herein. Such kits cancomprise a carrier, package, or container that is compartmentalized toreceive one or more containers such as vials, tubes, and the like, eachof the container(s) comprising one of the separate elements to be usedin a method described herein. Suitable containers include, for example,bottles, vials, syringes, and test tubes. The containers can be formedfrom a variety of materials such as glass or plastic.

For example, the container(s) can comprise one or more compoundsdescribed herein, optionally in a composition or in combination withanother agent as disclosed herein. The container(s) optionally have asterile access port (for example the container can be an intravenoussolution bag or a vial having a stopper pierceable by a hypodermicinjection needle). Such kits optionally comprise a compound with anidentifying description or label or instructions relating to its use inthe methods described herein.

A kit will typically comprise one or more additional containers, eachwith one or more of various materials (such as reagents, optionally inconcentrated form, and/or devices) desirable from a commercial and userstandpoint for use of a compound described herein. Non-limiting examplesof such materials include, but are not limited to, buffers, diluents,filters, needles, syringes; carrier, package, container, vial and/ortube labels listing contents and/or instructions for use, and packageinserts with instructions for use. A set of instructions will alsotypically be included.

A label can be on or associated with the container. A label can be on acontainer when letters, numbers or other characters forming the labelare attached, molded or etched into the container itself; a label can beassociated with a container when it is present within a receptacle orcarrier that also holds the container, e.g., as a package insert. Alabel can be used to indicate that the contents are to be used for aspecific therapeutic application. The label can also indicate directionsfor use of the contents, such as in the methods described herein. Theseother therapeutic agents may be used, for example, in the amountsindicated in the Physicians' Desk Reference (PDR) or as otherwisedetermined by one of ordinary skill in the art.

The invention is further illustrated by the following examples:

EXAMPLE 1 d₁₂-2-(2-Chlorophenyl)-2-methylamino-cyclohexanone(d₁₂-Ketamine)

Step 1

d₉-(2-Chlorophenyl)-cyclopentyl-methanone: The procedure of Step 1 iscarried out as described in U.S. Pat. No. 3,254,124.d₉-Cyclopentylbromide (about 120 g; available commercially fromSigma-Aldrich, St. Louis Mo. 63103) and magnesium turnings (about 19.4g) are used to make the corresponding Grignard reagent, which is thenreacted with 2-chlorobenzonitrile for about 3 days and hydrolyzed usingd₁-hydrochloric acid in deuterium oxide to give the title product.

Step 2

d₈-(1-Bromocyclopentyl)-(2-chlorophenyl)-methanone: The procedure ofStep 2 is carried out as described in U.S. Pat. No. 3,254,124.d₉-(2-Chlorophenyl)-cyclopentyl-methanone (about 21 g) is treated withbromine (about 10 g) in carbon tetrachloride (about 80 mL). The titleproduct is isolated by standard extractive workup and used immediatelyin the next step without any further purification.

Step 3

d₁₁-1-[(2-Chlorophenyl)-methylimino-methyl]-cyclopentanol: The procedureof Step 3 is carried out as described in U.S. Pat. No. 3,254,124.d₈-(1-Bromocyclopentyl)-(2-chlorophenyl)-methanone (about 30 g) istreated with liquid d₈-methylamine (about 50 mL; d₅-Methylamine gas iscommercially available from Sigma-Aldrich, St. Louis Mo. 63103). Afterabout 1 hour, the excess d₅-methylamine is removed in vacuo and theresulting residue is dissolved in pentane. The solvent is removed invacuo to give the title product.

Step 4

d₁₁-2-(2-Chlorophenyl)-2-methylamino-cyclohexanone (d₁₁-Ketamine): Theprocedure of Step 4 is carried out as described in U.S. Pat. No.3,254,124. d₁₁-1-[(2-chlorophenyl)-methylimino-methyl]-cyclopentanol (2g) is dissolved in decalin (15 mL) and heated at reflux for about 2.5hours. The solvent is removed in vacuo and the resulting crude residueis extracted into dilute hydrochloric acid. The solution is treated withdecolorizing charcoal and the pH is adjusted to greater than 7 with asolution of sodium hydroxide, to give the title product.

Step 5

d₁₂-2-(2-Chlorophenyl)-2-methylamino-cyclohexanone (d₁₂-Ketamine): Theprocedure of Step 5 is carried out as in Hopfgartner et al., J. Mass.Spectrom. 1996, 31, 69-76. At ambient temperature, d₁₁-ketamine is takenup in a 1:1 mixture of deuterium oxide and dioxane, the reaction ismaintained at ambient temperature until the disappearance of theexchangeable amide proton, as monitored by ¹H-NMR.

EXAMPLE 2 d₃-2-(2-Chlorophenyl)-2-methylamino-cyclohexanonehydrochloride

Step 1

(1-Bromocyclopentyl)-(2-chlorophenyl)-methanone:(2-Chlorophenyl)-cyclopentyl-methanone (1 g, 4.80 mmol) was treated withcopper(II) bromide (2.7 g, 12.09 mmol) in ethyl acetate (10 mL). Themixture was heated at about 80° C. for about 2.5 hours. The mixture wasfiltered, the filtrate was evaporated, and the crude residue was washedwith hexane to give the title product (1.25 g, 91%). ¹H NMR (300 MHz,CDCl₃) δ 7.72 (d, J=7.5 Hz, 1H), 7.46-7.28 (m, 3H), 2.46-2.29 (m, 4H),2.03-1.93 (m, 2H), 1.90-1.83 (m, 2H); LC-MS: m/z=288 (MH)⁺.

Step 2

d₃-1-[(2-Chlorophenyl)-methylimino-methyl]-cyclopentanol hydrochloride:At about −30° C., (1-Bromocyclopentyl)-(2-chlorophenyl)-methanone (1 g,3.48 mmol) was treated with liquid methylamine (approx. 2 mL). Afterabout 1 hour, the excess methylamine was evaporated, and the resultingresidue was dissolved in hexane and re-evaporated. The residue wasdissolved in diethyl ether (10 mL), and hydrochloride gas was pumped in.The resulting precipitate was collected by filtration to give the titleproduct (700 mg, 73%). ¹H NMR (300 MHz, CD₃OD) δ 7.76-7.49 (m, 3H),2.47-1.74 (m, 8H); LC-MS: m/z=241 (MH)⁺.

Step 3

d₃-2-(2-Chlorophenyl)-2-methylamino-cyclohexanone hydrochloride:d₃-1-[(2-Chlorophenyl)-methylimino-methyl]-cyclopentanol hydrochloride(400 mg, 1.4 mmol) was dissolved in ethyl benzoate (5 mL) and heated atabout 170° C. for about 30 minutes. Hexane was then added and the crudeproduct was collected by filtration. Recrystallisation frommethanol-ether gave the title product (200 mg, 50%). ¹H NMR (300 MHz,CDCl₃) δ 10.57-10.53 (m, 1H), 9.49-9.46 (m, 1H), 8.01 (d, J=7.8 Hz, 1H),7.55-7.42 (m, 3H), 3.53-3.49 (m, 1H), 2.69-2.46 (m, 3H), 2.00-1.84 (m,3H), 1.65-1.51 (m, 1H); LC-MS : m/z=241 (MH)⁺; HPLC: 98% (Purity).

EXAMPLE 3 d₁₁-2-(2-Chlorophenyl)-2-methylamino-cyclohexanonehydrochloride

Step 1

d₈-(2-Chlorophenyl)-cyclopentyl-methanone: d₉-Cyclopentylbromide (2 g,13.4 mmol) and magnesium turnings (1.85 g, 77.1 mmol) were used to makethe corresponding Grignard reagent, which was then mixed with2-chlorobenzonitrile (1.85 g, 13.2 mmol), copper (I) bromide (100 mg,0.7 mmol) and diethyl ether (40 mL). The mixture was heated at refluxfor about 16 hours and then hydrolyzed for about 2 hours at ambienttemperature using 6N hydrochloric acid (10 mL). After standardextractive workup, the crude product was purified by columnchromatography on silica gel (petroleum ether-ethyl acetate=70/1, v/v,elution) to give the title product. ¹H NMR (300 MHz, CDCl₃) δ 7.69-7.26(m, 4H), 3.55 (s, 1H); LC-MS: m/z=217 (MH)⁺.

Step 2

d₈-(1-Bromocylopentyl)-(2-chlorophenyl)-methanone:d₈-(2-Chlorophenyl)-cyclopentyl-methanone (400 mg, 1.84 mmol) wastreated with copper (II) bromide (1.22 g, 5.46 mmol) in ethyl acetate(40 mL). The mixture was heated at about 80° C. for about 2.5 hours. Themixture was filtered, the filtrate was evaporated, and the crude residuewas washed with hexane to give the title product (450 mg, 83%). ¹H NMR(300 MHz, CDCl₃) δ 7.68 (d, 1H, J=7.8 Hz), 7.44-7.26 (m, 3H); LC-MS:m/z=297 (MH)⁺.

Step 3

d₁₁-1-[(2-Chlorophenyl)-methylimino-methyl]-cyclopentanol hydrochloride:At about −30° C., d₁₁-(1-Bromocyclopentyl)-(2-chlorophenyl)-methanone(450 mg, 1.52 mmol) was treated with liquid d₃-methylamine (about 2 mL).After about 1 hour, the excess methylamine was evaporated, and theresulting residue was dissolved in hexane and re-evaporated. The residuewas dissolved in diethyl ether (10 mL), and hydrochloride, gas waspumped in. The resulting precipitate was collected by filtration to givethe title product (150 mg, 35%). ¹H NMR (300 MHz, CD₃OD) δ 7.76-7.54 (m,4H); LC-MS: m/z=249 (MH)⁺.

Step 4

d₁₁-2-(2-Chlorophenyl)-2-methylamino-cyclohexanone hydrochloride:d₁₁-1-[(2-Chlorophenyl)-methylimino-methyl]-cyclopentanol hydrochloride(150 mg, 0.5 mmol) was dissolved in ethyl benzoate (5 mL) and heated atabout 170° C. for about 30 minutes. Hexane was then added, and the crudeproduct was collected by filtration. Recrystallization withmethanol-ether gave the title product (30 mg, 20%). ¹H NMR (300 MHz,CDCl₃) δ 10.53 (br.s, 1H), 9.48 (br.s, 1H), 8.01 (d, 1H, J=7.8 Hz),7.56-7.42 (m, 3H), 2.68-2.53 (m, 2H); LC-MS: m/z=247 (MH)⁺; HPLC: 90%(Purity).

The following compounds can generally be made using the methodsdescribed above. It is expected that these compounds when made will haveactivity similar to those that have been made in the examples above.

or a pharmaceutically acceptable salt, solvate, or prodrug thereof.

Changes in the metabolic properties of the compounds of Examples 1 to 3and its analogs as compared to its non-isotopically enriched analogs canbe shown using the following assays. Other compounds listed above, whichhave not yet been made and/or tested, are predicted to have changedmetabolic properties as shown by one or more of these assays as well.

EXAMPLE 4 In vitro Liver Microsomal Stability Assay

Liver microsomal stability assays were conducted at 1 mg per mL livermicrosome protein with a NADPH-generating system (2.2 mM NADPH, 25.6 mMglucose 6-phosphate, 6 units per mL glucose 6-phosphate dehydrogenaseand 3.3 mM MgCl₂) in a 2% sodium bicarbonate solution. Test compoundswere dissolved in 20% acetonitrile-water and added to the assay mixture(final assay concentration 1 μM). The final concentration ofacetonitrile in the assay should be <1%. The samples were incubated atabout 37° C. Aliquots (50 μL) were taken out at times 0, 15, 30, 45, and60 min and ice cold acetonitrile (200 μL) was added to quench thereactions. Samples were centrifuged at 12,000 RPM for about 10 min toprecipitate the proteins. Supernatants were then transferred to microcentrifuge tubes and stored for degradation half-life analysis byLC/MS/MS. It has thus been found that the compounds as disclosed hereinaccording to the present invention that have been tested in this assayshowed an increase of 10% or more in the degradation half-life, ascompared to the non-isotopically enriched drug. For example, thedegradation half-lives of the compounds of Example 2 and Example 3 wereincreased by 10-166%, as compared to non-isotopically enriched ketamine.

EXAMPLE 5 In vitro Metabolism Using Human Cytochrome P₄₅₀ Enzymes

The cytochrome P₄₅₀ enzymes are expressed from the corresponding humancDNA using a baculovirus expression system (BD Biosciences, San Jose,Calif.). A 0.25 milliliter reaction mixture containing 0.8 milligramsper milliliter protein, 1.3 millimolar NADP⁺, 3.3 millimolarglucose-6-phosphate, 0.4 U/mL glucose-6-phosphate dehydrogenase, 3.3millimolar magnesium chloride and 0.2 millimolar of a compound asdisclosed herein, the corresponding non-isotopically enriched compoundor standard or control in 100 millimolar potassium phosphate (pH 7.4) isincubated at 37° C. for 20 min. After incubation, the reaction isstopped by the addition of an appropriate solvent (e.g., acetonitrile,20% trichloroacetic acid, 94% acetonitrile/6% glacial acetic acid, 70%perchloric acid, 94% acetonitrile/6% glacial acetic acid) andcentrifuged (10,000 g) for 3 min. The supernatant is analyzed byHPLC/MS/MS.

Cytochrome P₄₅₀ Standard CYP1A2 Phenacetin CYP2A6 Coumarin CYP2B6[¹³C]-(S)-mephenytoin CYP2C8 Paclitaxel CYP2C9 Diclofenac CYP2C19[¹³C]-(S)-mephenytoin CYP2D6 (+/−)-Bufuralol CYP2E1 Chlorzoxazone CYP3A4Testosterone CYP4A [¹³C]-Lauric acid

EXAMPLE 6 Monoamine Oxidase A Inhibition and Oxidative Turnover

The procedure is carried out as described in Weyler, Journal ofBiological Chemistry 1985, 260, 13199-13207. Monoamine oxidase Aactivity is measured spectrophotometrically by monitoring the increasein absorbance at 314 nm on oxidation of kynuramine with formation of4-hydroxyquinoline. The measurements are carried out, at 30° C., in 5 mMNaP_(i) buffer, pH 7.2, containing 0.2% Triton X-100 (monoamine oxidaseassay buffer), plus 1 mM kynuramine, and the desired amount of enzyme in1 mL total volume.

EXAMPLE 7 Monoamine Oxidase B Inhibition and Oxidative Turnover

The procedure is carried out as described in Uebelhack,Pharmacopsychiatry 1998, 31, 187-192.

EXAMPLE 8 Inhibition of [³H]TCP Binding to the Rat NMDA Receptor

The procedure is carried out as described in Goldman et al, FEBS Letters1985, 190(2), 333-336.

EXAMPLE 9 Rat Model for Hypoxia-Induced Neurodegeneration andNMDA-Antagonist Neuroprotection

The procedure is carried out as described in Reeker et al, CanadianJournal of Anaesthesia 2000, 37(6), 572-578.

The examples set forth above are disclosed to give a complete disclosureand description of how to make and use the claimed embodiments, and arenot intended to limit the scope of what the inventors regard as what isdisclosed herein. Modifications that are obvious are intended to bewithin the scope of the following claims. All publications, patents, andpatent applications cited in this specification are incorporated hereinby reference as if each such publication, patent or patent applicationwere specifically and individually indicated to be incorporated hereinby reference.

1. A compound having structural Formula I

or a pharmaceutically acceptable salt, solvate, or prodrug thereof;wherein: R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄,R₁₅, and R₁₆ are independently selected from the group consisting ofhydrogen and deuterium-, and at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇,R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ is deuterium.
 2. Thecompound as recited in claim 1, wherein said compound is substantially asingle enantiomer, a mixture of about 90% or more by weight of the(−)-enantiomer and about 10% or less by weight of the (+)-enantiomer, amixture of about 90% or more by weight of the (+)-enantiomer and about10% or less by weight of the (−)-enantiomer, substantially an individualdiastereomer, or a mixture of about 90% or more by weight of anindividual diastereomer and about 10% or less by weight of any otherdiastereomer.
 3. The compound as recited in claim 1, wherein at leastone of R₁, R₂, R₃, R4, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅,and R₁₆ independently has deuterium enrichment of no less than about98%.
 4. The compound as recited in claim 1, wherein at least one of R₁,R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆independently has deuterium enrichment of no less than about 90%.
 5. Thecompound as recited in claim 1, wherein at least one of R₁, R₂, R₃, R₄,R₅, R₆, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ independentlyhas deuterium enrichment of no less than about 50%.
 6. The compound asrecited in claim 1, wherein at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇,R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ independently hasdeuterium enrichment of no less than about 20%.
 7. The compound asrecited in claim 1, wherein at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇,R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ independently hasdeuterium enrichment of no less than about 10%.
 8. The compound asrecited in claim 1, wherein at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇,R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ independently hasdeuterium enrichment of no less than about 5%.
 9. The compound asrecited in claim 1, wherein at least one of R₁, R₂, R₃, R₄, R₅, R₆, R₇,R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄, R₁₅, and R₁₆ independently hasdeuterium enrichment of no less than about 1%.
 10. The compound asrecited in claim 1, wherein the compound is selected from the groupconsisting of:

or a pharmaceutically acceptable salt, solvate, or prodrug thereof. 11.The compound as recited in claim 10, wherein said compound issubstantially a single enantiomer, a mixture of about 90% or more byweight of the (−)-enantiomer and about 10% or less by weight of the(+)-enantiomer, a mixture of about 90% or more by weight of the(+)-enantiomer and about 10% or less by weight of the (−)-enantiomer,substantially an individual diastereomer, or a mixture of about 90% ormore by weight of an individual diastereomer and about 10% or less byweight of any other diastereomer.
 12. The compound as recited in claim10, wherein each of said positions represented as D have deuteriumenrichment of at least 98%.
 13. The compound as recited in claim 10,wherein each of said positions represented as D have deuteriumenrichment of at least 90%.
 14. The compound as recited in claim 10,wherein each of said positions represented as D have deuteriumenrichment of at least 50%.
 15. The compound as recited in claim 10,wherein each of said positions represented as D have deuteriumenrichment of at least 20%.
 16. The compound as recited in claim 10,wherein each of said positions represented as D have deuteriumenrichment of at least 10%.
 17. The compound as recited in claim 10,wherein each of said positions represented as D have deuteriumenrichment of at least 5%.
 18. The compound as recited in claim 10,wherein each of said positions represented as D have deuteriumenrichment of at least 1%.
 19. The compound as recited in claim 1,wherein the compound is selected from the group consisting of:


20. The compound as recited in claim 19, wherein said compound issubstantially a single enantiomer, a mixture of about 90% or more byweight of the (−)-enantiomer and about 10% or less by weight of the(+)-enantiomer, a mixture of about 90% or more by weight of the(+)-enantiomer and about 10% or less by weight of the (−)-enantiomer,substantially an individual diastereomer, or a mixture of about 90% ormore by weight of an individual diastereomer and about 10% or less byweight of any other diastereomer.
 21. The compound as recited in claim19, wherein each of said positions represented as D have deuteriumenrichment of at least 98%.
 22. The compound as recited in claim 19,wherein each of said positions represented as D have deuteriumenrichment of at least 90%.
 23. The compound as recited in claim 19,wherein each of said positions represented as D have deuteriumenrichment of at least 50%.
 24. The compound as recited in claim 19,wherein each of said positions represented as D have deuteriumenrichment of at least 20%.
 25. The compound as recited in claim 19,wherein each of said positions represented as D have deuteriumenrichment of at least 10%.
 26. The compound as recited in claim 19,wherein each of said positions represented as D have deuteriumenrichment of at least 5%.
 27. The compound as recited in claim 19,wherein each of said positions represented as D have deuteriumenrichment of at least 1%.
 28. A pharmaceutical composition comprisingthe compound as recited in claim 1 and one or more pharmaceuticallyacceptable carriers.
 29. A pharmaceutical composition as recited inclaim 28, further comprising one or more release-controlling excipients.30. The pharmaceutical composition as recited in claim 28, furthercomprising one or more non-release controlling excipients.
 31. Thepharmaceutical composition as recited in claim 28, wherein thecomposition is suitable for oral, parenteral, or intravenous infusionadministration.
 32. The pharmaceutical composition as recited in claim31, wherein the oral dosage form is a tablet or capsule.
 33. Thepharmaceutical composition as recited in claim 31, wherein the compoundis administered in a dose of about 0.5 milligram to about 1,000milligram.
 34. The pharmaceutical composition as recited in claim 28,further comprising another therapeutic agent.
 35. The pharmaceuticalcomposition as recited in claim 34, wherein the therapeutic agent isselected from the group consisting of NMDA receptor modulators, opioids,anesthetics, benzodiazepines, peripherally acting muscle relaxants,endothelin converting enzyme (ECE) inhibitors, thromboxane enzymeantagonists, potassium channel openers, thrombin inhibitors, growthfactor inhibitors, platelet activating factor (PAF) antagonists,anti-platelet agents, Factor VIIa Inhibitors, Factor Xa Inhibitors,renin inhibitors, neutral endopeptidase (NEP) inhibitors, vasopepsidaseinhibitors, HMG CoA reductase inhibitors, squalene synthetaseinhibitors, fibrates, bile acid sequestrants, anti-atheroscleroticagents, MTP Inhibitors, calcium channel blockers, potassium channelactivators, alpha-PDE5 agents, beta-PDE5 agents, antiarrhythmic agents,diuretics, anti-diabetic agents, PPAR-gamma agonists, mineralocorticoidenzyme antagonists, aP2 inhibitors, protein tyrosine kinase inhibitors,antiinflammatories, antiproliferatives, chemotherapeutic agents,immunosuppressants, anticancer agents, cytotoxic agents,antimetabolites, farnesyl-protein transferase inhibitors, hormonalagents, microtubule-disruptor agents, microtubule-stablizing agents,topoisomerase inhibitors, prenyl-protein transferase inhibitors,cyclosporins, TNF-alpha inhibitors, cyclooxygenase-2 (COX-2) inhibitors,gold compounds, and platinum coordination complexes.
 36. Thepharmaceutical composition as recited in claim 35, wherein thetherapeutic agent is a NMDA receptor modulator.
 37. The pharmaceuticalcomposition as recited in claim 36, wherein the NMDA receptor modulatoris selected from the group consisting of phencyclidine (PCP),amantadine, ibogaine, memantine, nitrous oxide, and dextromethorphan.38. The pharmaceutical composition as recited in claim 35, wherein thetherapeutic agent is an opioid.
 39. The pharmaceutical composition asrecited in claim 38, wherein the opioid is selected from the groupconsisting of morphine, codeine, thebain, diacetylmorphine, oxycodone,hydrocodone, hydromorphone, oxymorphone, nicomorphine, fentanyl,α-methylfentanyl, alfentanil, sufentanil, remifentanyl, carfentanyl,ohmefentanyl, pethidine, ketobemidone, propoxyphene, dextropropoxyphene,methadone, loperamide, pentazocine, buprenorphine, etorphine,butorphanol, nalbufine, levorphanol, naloxone, naltrexone, and tramadol.40. The pharmaceutical composition as recited in claim 35, wherein thetherapeutic agent is an anesthetic.
 41. The pharmaceutical compositionas recited in claim 40, wherein the anesthetic is selected from thegroup consisting of diethyl ether, vinyl ether, halothane, chloroform,methoxyflurane, enflurane, trichloroethylene, isoflurane, desflurane,sevoflurane, methohexital, hexobarbital, thiopental, narcobarbital,fentanyl, alfentanil, sufentanil, phenoperidine, anileridine,remifentanil, droperidol, ketamine, propanidid, alfaxalone, etomidate,propofol, hydroxybutyric acid, nitrous oxide, esketamine,metabutethamine, procaine, tetracaine, chloroprocaine, benzocaine,bupivacaine, lidocaine, mepivacaine, prilocaine, butanilicaine,cinchocaine, etidocaine, articaine, ropivacaine, levobupivacaine,cocaine, ethyl chloride, dyclonine, phenol, and capsaicin.
 42. Thepharmaceutical composition as recited in claim 35, wherein thetherapeutic agent is a benzodiazepine.
 43. The pharmaceuticalcomposition as recited in claim 42, wherein the benzodiazepine isselected from the group consisting of alprazolam, bromazepam,clonazepam, diazepam, estazolam, flunitrazepam, lorazepam, midazolam,nitrazepam, oxazepam, triazolam, temazepam, and chlordiazepoxide. 44.The pharmaceutical composition as recited in claim 35, wherein thetherapeutic agent is a peripherally acting muscle relaxant.
 45. Thepharmaceutical composition as recited in claim 44, wherein theperipherally acting muscle relaxant is selected from the groupconsisting of alcuronium, dimethyltubocurarine, tubocurarine,suxamethonium, atracurium, cisatracurium, doxacurium chloride,fazadinium bromide, gallamine, hexafluronium, mivacurium chloride,pancuronium, pipecuronium bromide, rocuronium bromide, vecuronium, andbotulinum toxin.
 46. A pharmaceutical composition comprising thecompound as recited in claim 19, and one or more pharmaceuticallyacceptable carriers.
 47. A pharmaceutical composition as recited inclaim 46, further comprising one or more release-controlling excipients.48. The pharmaceutical composition as recited in claim 46, furthercomprising one or more non-release controlling excipients.
 49. Thepharmaceutical composition as recited in claim 46, wherein thecomposition is suitable for oral, parenteral or intravenous infusionadministration.
 50. The pharmaceutical composition as recited in claim49, wherein the oral dosage form is a tablet, or capsule.
 51. Thepharmaceutical composition as recited in claim 49, wherein the compoundis administered in a dose of about 0.5 milligrams to about 1,000milligrams.
 52. The pharmaceutical composition as recited in claim 46,further comprising another therapeutic agent.
 53. The pharmaceuticalcomposition as recited in claim 52, wherein the therapeutic agent isselected from the group consisting of NMDA receptor modulators, opioids,anesthetics, benzodiazepines, peripherally acting muscle relaxants,endothelin converting enzyme (ECE) inhibitors, thromboxane enzymeantagonists, potassium channel openers, thrombin inhibitors, growthfactor inhibitors, platelet activating factor (PAF) antagonists,anti-platelet agents, Factor VIIa Inhibitors, Factor Xa Inhibitors,renin inhibitors, neutral endopeptidase (NEP) inhibitors, vasopepsidaseinhibitors, HMG CoA reductase inhibitors, squalene synthetaseinhibitors, fibrates, bile acid sequestrants, anti-atheroscleroticagents, MTP Inhibitors, calcium channel blockers, potassium channelactivators, alpha-PDE5 agents, beta-PDE5 agents, antiarrhythmic agents,diuretics, anti-diabetic agents, PPAR-gamma agonists, mineralocorticoidenzyme antagonists, aP2 inhibitors, protein tyrosine kinase inhibitors,antiinflammatories, antiproliferatives, chemotherapeutic agents,immunosuppressants, anticancer agents, cytotoxic agents,antimetabolites, farnesyl-protein transferase inhibitors, hormonalagents, microtubule-disruptor agents, microtubule-stablizing agents,topoisomerase inhibitors, prenyl-protein transferase inhibitors,cyclosporins, TNF-alpha inhibitors, cyclooxygenase-2 (COX-2) inhibitors,gold compounds, and platinum coordination complexes.
 54. Thepharmaceutical composition as recited in claim 53, wherein thetherapeutic agent is a NMDA receptor modulator.
 55. The pharmaceuticalcomposition as recited in claim 54, wherein the NMDA receptor modulatoris selected from the group consisting of phencyclidine (PCP),amantadine, ibogaine, memantine, nitrous oxide, and dextromethorphan.56. The pharmaceutical composition as recited in claim 53, wherein thetherapeutic agent is an opioid.
 57. The pharmaceutical composition asrecited in claim 56, wherein the opioid is selected from the groupconsisting of morphine, codeine, thebain, diacetylmorphine, oxycodone,hydrocodone, hydromorphone, oxymorphone, nicomorphine, fentanyl,α-methylfentanyl, alfentanil, sufentanil, remifentanyl, carfentanyl,ohmefentanyl, pethidine, ketobemidone, propoxyphene, dextropropoxyphene,methadone, loperamide, pentazocine, buprenorphine, etorphine,butorphanol, nalbufine, levorphanol, naloxone, naltrexone, and tramadol.58. The pharmaceutical composition as recited in claim 53, wherein thetherapeutic agent is an anesthetic.
 59. The pharmaceutical compositionas recited in claim 58, wherein the anesthetic is selected from thegroup consisting of diethyl ether, vinyl ether, halothane, chloroform,methoxyflurane, enflurane, trichloroethylene, isoflurane, desflurane,sevoflurane, methohexital, hexobarbital, thiopental, narcobarbital,fentanyl, alfentanil, sufentanil, phenoperidine, anileridine,remifentanil, droperidol, ketamine, propanidid, alfaxalone, etomidate,propofol, hydroxybutyric acid, nitrous oxide, esketamine,metabutethamine, procaine, tetracaine, chloroprocaine, benzocaine,bupivacaine, lidocaine, mepivacaine, prilocaine, butanilicaine,cinchocaine, etidocaine, articaine, ropivacaine, levobupivacaine,cocaine, ethyl chloride, dyclonine, phenol, and capsaicin.
 60. Thepharmaceutical composition as recited in claim 53, wherein thetherapeutic agent is a benzodiazepine.
 61. The pharmaceuticalcomposition as recited in claim 60, wherein the benzodiazepine isselected from the group consisting of alprazolam, bromazepam,clonazepam, diazepam, estazolam, flunitrazepam, lorazepam, midazolam,nitrazepam, oxazepam, triazolam, temazepam, and chlordiazepoxide. 62.The pharmaceutical composition as recited in claim 53, wherein thetherapeutic agent is a peripherally acting muscle relaxant.
 63. Thepharmaceutical composition as recited in claim 62, wherein theperipherally acting muscle relaxant is selected from the groupconsisting of alcuronium, dimethyltubocurarine, tubocurarine,suxamethonium, atracurium, cisatracurium, doxacurium chloride,fazadinium bromide, gallamine, hexafluronium, mivacurium chloride,pancuronium, pipecuronium bromide, rocuronium bromide, vecuronium, andbotulinum toxin.
 64. A method for the treatment, prevention, oramelioration of one or more symptoms of a NMDA receptor-mediateddisorder in a subject comprising administering a therapeuticallyeffective amount of a compound as recited in claim
 1. 65. The method asrecited in claim 64, wherein the NMDA receptor-mediated disorder isselected from the group consisting of nociceptive pain, neuropathicpain, phantom limb pain, ischemic pain, stroke, sepsis, inflammation,opioid tolerance, Alzheimer's disease, and burn.
 66. The method asrecited in claim 64, wherein the NMDA receptor-mediated disorder can belessened, alleviated, or prevented by using an agent selected from thegroup consisting of an anesthetic, analgesic, entheogen, therapeuticcataleptic, and neuroprotectant.
 67. The method as recited in claim 66,wherein the anesthetic promotes general anaesthesia.
 68. The method asrecited in claim 64, wherein the NMDA receptor-mediated disorder can belessened, alleviated, or prevented by administering a NDMA receptormodulator.
 69. The method as recited in claim 64, wherein said compoundhas at least one of the following properties: a) decreasedinter-individual variation in plasma levels of said compound or ametabolite thereof as compared to the non-isotopically enrichedcompound; b) increased average plasma levels of said compound per dosageunit thereof as compared to the non-isotopically enriched compound; c)decreased average plasma levels of at least one metabolite of saidcompound per dosage unit thereof as compared to the non-isotopicallyenriched compound; d) increased average plasma levels of at least onemetabolite of said compound per dosage unit thereof as compared to thenon-isotopically enriched compound; and e) an improved clinical effectduring the treatment in said subject per dosage unit thereof as comparedto the non-isotopically enriched compound.
 70. The method as recited inclaim 64, wherein said compound has at least two of the followingproperties: a) decreased inter-individual variation in plasma levels ofsaid compound or a metabolite thereof as compared to thenon-isotopically enriched compound; b) increased average plasma levelsof said compound per dosage unit thereof as compared to thenon-isotopically enriched compound; c) decreased average plasma levelsof at least one metabolite of said compound per dosage unit thereof ascompared to the non-isotopically enriched compound; d) increased averageplasma levels of at least one metabolite of said compound per dosageunit thereof as compared to the non-isotopically enriched compound; ande) an improved clinical effect during the treatment in said subject perdosage unit thereof as compared to the non-isotopically enrichedcompound.
 71. The method as recited in claim 64, wherein the methodaffects a decreased metabolism of the compound per dosage unit thereofby at least one polymorphically-expressed cytochrome P450 isoform in thesubject, as compared to the corresponding non-isotopically enrichedcompound.
 72. The method as recited in claim 71, wherein the cytochromeP₄₅₀ isoform is selected from the group consisting of CYP2C8, CYP2C9,CYP2C19, and CYP2D6.
 73. The method as recited in claim 64, wherein saidcompound is characterized by decreased inhibition of at least onecytochrome P₄₅₀ or monoamine oxidase isoform in said subject per dosageunit thereof as compared to the non-isotopically enriched compound. 74.The method as recited in claim 73, wherein said cytochrome P₄₅₀ ormonoamine oxidase isoform is selected from the group consisting ofCYP1A1, CYP1A2, CYP1B1, CYP2A6, CYP2A13, CYP2B6, CYP2C8, CYP2C9,CYP2C18, CYP2C19, CYP2D6, CYP2E1, CYP2G1, CYP2J2, CYP2R1, CYP2S1,CYP3A4, CYP3A5, CYP3A5P1, CYP3A5P2, CYP3A7, CYP4A11, CYP4B1, CYP4F2,CYP4F3, CYP4F8, CYP4F11, CYP4F12, CYP4X1, CYP4Z1, CYP5A1, CYP7A1,CYP7B1, CYP8A1, CYP8B1, CYP11A1, CYP11B1, CYP11B2, CYP17, CYP19, CYP21,CYP24, CYP26A1, CYP26B1, CYP27A1, CYP27B1, CYP39, CYP46, CYP51, MAO_(A),and MAO_(B).
 75. The method as recited in claim 64, wherein the methodaffects the treatment of the disease while reducing or eliminating adeleterious change in a diagnostic hepatobiliary function endpoint, ascompared to the corresponding non-isotopically enriched compound. 76.The method as recited in claim 75, wherein the diagnostic hepatobiliaryfunction endpoint is selected from the group consisting of alanineaminotransferase (“ALT”), serum glutamic-pyruvic transaminase (“SGPT”),aspartate aminotransferase (“AST,” “SGOT”), ALT/AST ratios, serumaldolase, alkaline phosphatase (“ALP”), ammonia levels, bilirubin,gamma-glutamyl transpeptidase (“GGTP,” “γ-GTP,” “GGT”), leucineaminopeptidase (“LAP”), liver biopsy, liver ultrasonography, livernuclear scan, 5′-nucleotidase, and blood protein.
 77. A method for thetreatment, prevention, or amelioration of one or more symptoms of a NDMAreceptor-mediated disorder in a subject, by administering atherapeutically effective amount of a compound as recited in claim 19.78. The method as recited in claim 77, wherein the NDMAreceptor-mediated disorder is selected from the group consisting ofnociceptive pain, neuropathic pain, phantom limb pain, ischemic pain,stroke, sepsis, inflammation, opioid tolerance, Alzheimer's disease, andburn.
 79. The method as recited in claim 77, wherein the NMDAreceptor-mediated disorder can be lessened, alleviated, or prevented byusing as agent selected from the group consisting of an anesthetic,analgesic, entheogen, therapeutic cataleptic, and neuroprotectant. 80.The method as recited in claim 79, wherein the anesthetic promotesgeneral anaesthesia.
 81. The method as recited in claim 77, wherein theNMDA receptor-mediated disorder can be lessened, alleviated, orprevented by administering a NDMA receptor modulator.
 82. The method asrecited in claim 77, wherein said compound has at least one of thefollowing properties: a) decreased inter-individual variation in plasmalevels of said compound or a metabolite thereof as compared to thenon-isotopically enriched compound; b) increased average plasma levelsof said compound per dosage unit thereof as compared to thenon-isotopically enriched compound; c) decreased average plasma levelsof at least one metabolite of said compound per dosage unit thereof ascompared to the non-isotopically enriched compound; d) increased averageplasma levels of at least one metabolite of said compound per dosageunit thereof as compared to the non-isotopically enriched compound; ande) an improved clinical effect during the treatment in said subject perdosage unit thereof as compared to the non-isotopically enrichedcompound.
 83. The method as recited in claim 77, wherein said compoundhas at least two of the following properties: a) decreasedinter-individual variation in plasma levels of said compound or ametabolite thereof as compared to the non-isotopically enrichedcompound; b) increased average plasma levels of said compound per dosageunit thereof as compared to the non-isotopically enriched compound; c)decreased average plasma levels of at least one metabolite of saidcompound per dosage unit thereof as compared to the non-isotopicallyenriched compound; d) increased average plasma levels of at least onemetabolite of said compound per dosage unit thereof as compared to thenon-isotopically enriched compound; and e) an improved clinical effectduring the treatment in said subject per dosage unit thereof as comparedto the non-isotopically enriched compound.
 84. The method as recited inclaim 77, wherein the method affects a decreased metabolism of thecompound per dosage unit thereof by at least onepolymorphically-expressed cytochrome P450 isoform in the subject, ascompared to the corresponding non-isotopically enriched compound. 85.The method as recited in claim 84, wherein the cytochrome P₄₅₀ isoformis selected from the group consisting of CYP2C8, CYP2C9, CYP2C19, andCYP2D6.
 86. The method as recited in claim 77, wherein said compound ischaracterized by decreased inhibition of at least one cytochrome P₄₅₀ ormonoamine oxidase isoform in said subject per dosage unit thereof ascompared to the non-isotopically enriched compound.
 87. The method asrecited in claim 86, wherein said cytochrome P₄₅₀ or monoamine oxidaseisoform is selected from the group consisting of CYP1A1, CYP1A2, CYP1B1,CYP2A6, CYP2A13, CYP2B6, CYP2C8, CYP2C9, CYP2C18, CYP2C19, CYP2D6,CYP2E1, CYP2G1, CYP2J2, CYP2R1, CYP2S1, CYP3A4, CYP3A5, CYP3A5P1,CYP3A5P2, CYP3A7, CYP4A11, CYP4B1, CYP4F2, CYP4F3, CYP4F8, CYP4F1,CYP4F12, CYP4X1, CYP4Z1, CYP5A1, CYP7A1, CYP7B1, CYP8A1, CYP8B1,CYP11A1, CYP11B1, CYP11B2, CYP17, CYP19, CYP21, CYP24, CYP26A1, CYP26B1,CYP27A1, CYP27B1, CYP39, CYP46, CYP51, MAO_(A), and MAO_(B).
 88. Themethod as recited in claim 77, wherein the method affects the treatmentof the disease while reducing or eliminating a deleterious change in adiagnostic hepatobiliary function endpoint, as compared to thecorresponding non-isotopically enriched compound.
 89. The method asrecited in claim 88, wherein the diagnostic hepatobiliary functionendpoint is selected from the group consisting of alanineaminotransferase (“ALT”), serum glutamic-pyruvic transaminase (“SGPT”),aspartate aminotransferase (“AST,” “SGOT”), ALT/AST ratios, serumaldolase, alkaline phosphatase (“ALP”), ammonia levels, bilirubin,gamma-glutamyl transpeptidase (“GGTP,” “γ-GTP,” “GGT”), leucineaminopeptidase (“LAP”), liver biopsy, liver ultrasonography, livernuclear scan, 5′-nucleotidase, and blood protein.